A touch screen linearity test method

Abstract

This invention relates to the field of touch screen testing and discloses a method for testing the linearity of touch screens. By constructing a Cartesian coordinate system for the testing platform and a Cartesian coordinate system for the touch screen, and detecting the positions of points A and B in the two coordinate systems respectively, the position of the touchable area can be accurately represented in the Cartesian coordinate system of the testing platform, thereby facilitating the planning of testing routes for touch screens of different sizes and specifications by the testing robot.

Description

Technical Field

[0001] This invention relates to the field of touchscreen testing, and more particularly to a method for testing the linearity of a touchscreen. Background Technology

[0002] Touchscreens are increasingly being used in 3C products such as mobile phones and tablets. Users can operate the device simply by touching icons or text on the touchscreen. Touchscreen technology has become the most convenient input device for human-computer interaction and is an important part of human-computer interaction; the quality of the touchscreen directly determines the performance of the device.

[0003] Among the various performance indicators of a touchscreen, linearity is the most important, as its accuracy directly affects the touchscreen's overall performance. Linearity testing refers to whether the touchscreen's response follows the same path as the drawn lines when lines are drawn across different areas of the touchscreen, and whether its accuracy meets the requirements.

[0004] Current touchscreen linearity testing methods involve a robotic arm moving along a preset path to test the touchscreen's linearity. The touchscreen needs to be fixed on the testing platform. Current touchscreen linearity testing methods can only test a few specific sizes of touchscreens, resulting in a narrow testing range. Furthermore, if the touchscreen is tilted, the robotic arm's testing path will deviate from the preset path relative to the touchscreen, leading to a decrease in testing accuracy.

[0005] Therefore, it is necessary to design a touch screen linearity testing method to improve the detection range of touch screens. Summary of the Invention

[0006] The purpose of this invention is to provide a method for testing the linearity of a touch screen, thereby improving the detection range of the touch screen.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] A method for testing the linearity of a touchscreen includes the following steps:

[0009] Fix the touch screen to the testing platform and construct a Cartesian coordinate system for the testing platform;

[0010] Obtain the touchscreen pixel resolution and the size of the touchable area. Construct a touchscreen Cartesian coordinate system based on the touchscreen pixel resolution and the size of the touchable area. The touchscreen Cartesian coordinate system includes a T-axis and a U-axis that are perpendicular to the T-axis. The T-axis coincides with one edge of the touchable area, and the U-axis coincides with the other edge of the touchable area.

[0011] Obtain the coordinates of points A and B in the touchable area in the Cartesian coordinate system of the touchscreen plane and the Cartesian coordinate system of the detection platform plane, respectively; where the coordinates of point A in the detection platform coordinate system are (Ax, Ay), and the coordinates of point A in the touchscreen coordinate system are (At, Au); the coordinates of point B in the detection platform coordinate system are (Bx, By), and the coordinates of point A in the touchscreen coordinate system are (Bt, Bu).

[0012] Based on the coordinates of points A and B in the Cartesian coordinate system of the touch screen and the Cartesian coordinate system of the detection platform, calculate the position of the touchable area in the Cartesian coordinate system of the detection platform.

[0013] Linearity detection paths are planned based on the position of the touchable area in the Cartesian coordinate system of the detection platform.

[0014] Optionally, the calculation of the position of the touchable area in the Cartesian coordinate system of the detection platform based on the coordinates of points A and B in the Cartesian coordinate system of the touchscreen plane and the coordinates in the Cartesian coordinate system of the detection platform plane specifically involves:

[0015] Establish the relative positional relationship between the touchscreen's Cartesian coordinate system and the detection platform's Cartesian coordinate system:

[0016] The coordinate transformation formulas between the touch screen's Cartesian coordinate system and the detection platform's Cartesian coordinate system are as follows:

[0017]

[0018] The detection platform's Cartesian coordinate system includes an X-axis and a Y-axis perpendicular to the X-axis. The angle between the T-axis and the X-axis is θ, and the angle between the U-axis and the Y-axis is θ, where 0 < θ < 90°.

[0019] Substituting the coordinates (Ax, Ay), (At, Au), (Bx, By), and (Bt, Bu) into the coordinate transformation formula, we obtain:

[0020]

[0021] Where Ex = Ax - Bx, Ey = Ay - By, Et = At ​​- Bt, Eu = Au - Bu;

[0022] The transformation yields:

[0023] Ex Et+Ey Eu=Et 2 cosθ+Eu 2 cosθ=(Et 2 +Eu 2 cosθ;

[0024] Ey Et-Ex Eu=Et2sinθ+Eu2sinθ=(Et 2 +Eu 2 sinθ;

[0025] Then we can get:

[0026] cosθ=(Ex Et+Ey Eu) / (Et 2 +Eu 2 );

[0027] sinθ=(Ey Et-Ex Eu) / (Et 2 +Eu 2 );

[0028] The origin of the Cartesian coordinate system of the touch screen is (Ox, Oy), where 0x = Ax - (At cosθ – Au sinθ) and Oy = Ay - (At sinθ - Av cosθ).

[0029] Based on the origin coordinates, coordinate transformation formula, specific values ​​of cosθ and sinθ of the detection platform's Cartesian coordinate system, the position of the touchable area in the Cartesian coordinate system of the detection platform is calculated.

[0030] Optionally, a linearity detection path is planned based on the position of the touchable area in the Cartesian coordinate system of the detection platform, including:

[0031] Calculate the coordinates of the four vertex pixels of the touchable area in the Cartesian coordinate system of the detection platform plane;

[0032] Choose any two of the four vertex pixels as the start and end points of the linearity detection path.

[0033] Optionally, the linearity detection path includes a first detection route, a second detection route, a third detection route, and a fourth detection route:

[0034] The first detection route is parallel to the third detection route, and the second detection route intersects with the fourth detection route: the end point of the first detection route is the start point of the second detection route, and the end point of the second detection route is the start point of the third detection route; the end point of the third detection route is the start point of the fourth detection route, and the end point of the fourth detection route is the start point of the first detection route.

[0035] Optionally, a number of test pixels are set along the linearity detection path;

[0036] The test checks whether the deviation between the actual coordinates of the test pixel and the linearity detection path exceeds a preset allowable value; if so, an alarm is triggered and the test ends.

[0037] Optionally, the touchscreen is placed on the inspection platform and a Cartesian coordinate system is constructed for the inspection platform, including:

[0038] Place the touchscreen on the testing platform with the screen facing away from the surface of the testing platform;

[0039] The first side of the detection platform is taken as the X-axis, the second side perpendicular to the first side is taken as the Y-axis, and the point where the first side and the second side intersect is taken as the origin of the coordinate system.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] In this embodiment, by constructing a Cartesian coordinate system for the detection platform and a Cartesian coordinate system for the touch screen, and detecting the positions of points A and B in the two coordinate systems respectively, the position of the touchable area can be accurately represented in the Cartesian coordinate system of the detection platform, thereby facilitating the robot arm to plan the detection route for touch screens of different sizes and specifications. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0044] Figure 1 This is a schematic diagram showing the positions of the detection platform in a Cartesian coordinate system and the touchscreen in a Cartesian coordinate system provided in an embodiment of the present invention.

[0045] Figure 2 A flowchart illustrating the touchscreen linearity testing method provided in this embodiment of the invention. Detailed Implementation

[0046] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0047] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.

[0048] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0049] This invention provides a method for testing the linearity of a touchscreen, comprising the following steps:

[0050] S01. Fix the touch screen on the testing platform and construct a Cartesian coordinate system for the testing platform;

[0051] S02. Obtain the touch screen pixel resolution and the size of the touchable area. Construct a touch screen plane rectangular coordinate system based on the touch screen pixel resolution and the size of the touchable area. The touch screen plane rectangular coordinate system includes a T-axis and a U-axis that are perpendicular to the T-axis. The T-axis coincides with one edge of the touchable area, and the U-axis coincides with the other edge of the touchable area.

[0052] S03. Obtain the coordinates of points A and B in the touchable area in the Cartesian coordinate system of the touch screen and the Cartesian coordinate system of the detection platform, respectively; wherein, the coordinates of point A in the detection platform coordinate system are (Ax, Ay), and the coordinates of point A in the touch screen coordinate system are (At, Au); the coordinates of point B in the detection platform coordinate system are (Bx, By), and the coordinates of point A in the touch screen coordinate system are (Bt, Bu).

[0053] S04. Based on the coordinates of points A and B in the Cartesian coordinate system of the touch screen and the coordinates in the Cartesian coordinate system of the detection platform, calculate the position of the touchable area in the Cartesian coordinate system of the detection platform.

[0054] S05. Plan the linearity detection path based on the position of the touchable area in the Cartesian coordinate system of the detection platform.

[0055] In this embodiment, by constructing a Cartesian coordinate system for the touch screen based on pixels, the position of the touchable area in the Cartesian coordinate system of the detection platform is calculated based on the positions of points A and B, which helps the detection robot to better plan the detection route.

[0056] In actual testing, the touch screen can be placed flat and fixed on the testing platform for testing, regardless of whether the touch screen is horizontal or vertical. This significantly reduces the requirements for the fixation and size of the touch screen, which helps to improve testing efficiency and testing range, and can effectively avoid testing deviations caused by fixation deviations.

[0057] Optionally, the calculation of the position of the touchable area in the Cartesian coordinate system of the detection platform based on the coordinates of points A and B in the Cartesian coordinate system of the touchscreen plane and the coordinates in the Cartesian coordinate system of the detection platform plane specifically involves:

[0058] S041. Establish the relative positional relationship between the touchscreen's Cartesian coordinate system and the detection platform's Cartesian coordinate system:

[0059] The coordinate transformation formulas between the touch screen's Cartesian coordinate system and the detection platform's Cartesian coordinate system are as follows:

[0060]

[0061] The detection platform's Cartesian coordinate system includes an X-axis and a Y-axis perpendicular to the X-axis. The angle between the T-axis and the X-axis is θ, and the angle between the U-axis and the Y-axis is θ, where 0 < θ < 90°.

[0062] Substituting the coordinates (Ax, Ay), (At, Au), (Bx, By), and (Bt, Bu) into the coordinate transformation formula, we obtain:

[0063]

[0064] Where Ex = Ax - Bx, Ey = Ay - By, Et = At ​​- Bt, Eu = Au - Bu;

[0065] The transformation yields:

[0066] Ex Et+Ey Eu=Et 2 cosθ+Eu 2 cosθ=(Et 2 +Eu 2 cosθ;

[0067] Ey Et-Ex Eu=Et2sinθ+Eu2sinθ=(Et 2 +Eu 2 sinθ;

[0068] Then we can get:

[0069] cosθ=(Ex Et+Ey Eu) / (Et 2 +Eu 2 );

[0070] sinθ=(Ey Et-Ex Eu) / (Et 2 +Eu 2 );

[0071] The origin of the Cartesian coordinate system of the touch screen is (Ox, Oy), where 0x = Ax - (At cosθ – Au sinθ) and Oy = Ay - (At sinθ - Av cosθ).

[0072] S042. Based on the origin coordinates, coordinate transformation formula, specific values ​​of cosθ and sinθ of the detection platform's Cartesian coordinate system, calculate the position of the touchable area in the Cartesian coordinate system of the detection platform.

[0073] In one specific implementation, the size of the touchscreen Active Area (AA) is 176.18mm × 99.36mm, and the pixel resolution is 1920 × 1080.

[0074] (X, Y): Coordinates of the touchscreen online testing machine

[0075] The coordinates of the online measuring machine at points A and B, where the CCD detection device is positioned, are: (Ax, Ay) (40.5mm, 28.0mm) and (Bx, By) (180.6mm, 90.30mm).

[0076] (At, Au) and (Bt, Bu) are the rectangular coordinates of points A and B on the touchscreen plane, respectively.

[0077] The coordinates of points A and B relative to the origin O on the engineering drawing are (At, Au) (20.5mm, 18.0mm) and (Bt, Bu) (160.6mm, 80.3mm), respectively.

[0078] Knowing the coordinates of points A and B in the Cartesian coordinate system of the touchscreen plane, we can deduce 1920 / 176.18 = w / t and 1080 / 99.36 = h / u. At this point, (w, h) is the position of the pixel in the Cartesian coordinate system of the touchscreen plane.

[0079] Therefore, t = 0.09176w, u = 0.092h. Substituting these values, we get:

[0080]

[0081] Based on the above formula, the positions of the four corner pixels of the touch screen in the coordinate system can be calculated, which makes it easier for the robot arm to find the right position for detection.

[0082] In this embodiment, the position of the touchable area relative to the Cartesian coordinate system of the detection platform can be accurately detected without detecting the angular and positional deviations between the Cartesian coordinate system of the detection platform and the Cartesian coordinate system of the touch screen. This allows the robot arm to accurately plan its movement path and travel distance.

[0083] Optionally, a linearity detection path is planned based on the position of the touchable area in the Cartesian coordinate system of the detection platform, including:

[0084] Calculate the coordinates of the four vertex pixels of the touchable area in the Cartesian coordinate system of the detection platform plane;

[0085] Choose any two of the four vertex pixels as the start and end points of the linearity detection path.

[0086] In a practical linearity detection path, multiple paths can be included to make the linearity detection more accurate and improve the detection precision of the touch screen's linearity.

[0087] Optionally, the linearity detection path includes a first detection route, a second detection route, a third detection route, and a fourth detection route:

[0088] The first detection route is parallel to the third detection route, and the second detection route intersects with the fourth detection route: the end point of the first detection route is the start point of the second detection route, and the end point of the second detection route is the start point of the third detection route; the end point of the third detection route is the start point of the fourth detection route, and the end point of the fourth detection route is the start point of the first detection route.

[0089] Optionally, a number of test pixels are set along the linearity detection path;

[0090] The test checks whether the deviation between the actual coordinates of the test pixel and the linearity detection path exceeds a preset allowable value; if so, an alarm is triggered and the test ends.

[0091] During the actual testing process, if the deviation between the actual coordinates of the test pixel and the linearity detection path exceeds the preset allowable value, it indicates that the linearity of the touch screen is poor and does not meet the requirements. Therefore, it is judged as a defective product and the test ends.

[0092] Optionally, the touchscreen is placed on the inspection platform and a Cartesian coordinate system is constructed for the inspection platform, including:

[0093] Place the touchscreen on the testing platform with the screen facing away from the surface of the testing platform;

[0094] The first side of the detection platform is taken as the X-axis, the second side perpendicular to the first side is taken as the Y-axis, and the point where the first side and the second side intersect is taken as the origin of the coordinate system.

[0095] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0096] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

[0097] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for testing the linearity of a touchscreen, characterized in that, Including the following steps: Fix the touch screen to the testing platform and construct a Cartesian coordinate system for the testing platform; Obtain the touchscreen pixel resolution and the size of the touchable area. Construct a touchscreen Cartesian coordinate system based on the touchscreen pixel resolution and the size of the touchable area. The touchscreen Cartesian coordinate system includes a T-axis and a U-axis that are perpendicular to the T-axis. The T-axis coincides with one edge of the touchable area, and the U-axis coincides with the other edge of the touchable area. Obtain the coordinates of points A and B in the touchable area in the Cartesian coordinate system of the touchscreen plane and the Cartesian coordinate system of the detection platform plane, respectively; where the coordinates of point A in the detection platform coordinate system are (Ax, Ay), and the coordinates of point A in the touchscreen coordinate system are (At, Au); the coordinates of point B in the detection platform coordinate system are (Bx, By), and the coordinates of point A in the touchscreen coordinate system are (Bt, Bu). Based on the coordinates of points A and B in the Cartesian coordinate system of the touch screen and the Cartesian coordinate system of the detection platform, calculate the position of the touchable area in the Cartesian coordinate system of the detection platform. Linearity detection paths are planned based on the position of the touchable area in the Cartesian coordinate system of the detection platform.

2. The touchscreen linearity testing method according to claim 1, characterized in that, The position of the touchable area in the Cartesian coordinate system of the detection platform is calculated based on the coordinates of points A and B in the Cartesian coordinate system of the touchscreen and the Cartesian coordinate system of the detection platform. Specifically: Establish the relative positional relationship between the touchscreen's Cartesian coordinate system and the detection platform's Cartesian coordinate system: The coordinate transformation formulas between the touch screen's Cartesian coordinate system and the detection platform's Cartesian coordinate system are as follows: The detection platform's Cartesian coordinate system includes an X-axis and a Y-axis perpendicular to the X-axis. The angle between the T-axis and the X-axis is θ, and the angle between the U-axis and the Y-axis is θ, where 0 < θ < 90°. Substituting the coordinates (Ax, Ay), (At, Au), (Bx, By), and (Bt, Bu) into the coordinate transformation formula, we obtain: Where Ex = Ax - Bx, Ey = Ay - By, Et = At ​​- Bt, Eu = Au - Bu; The transformation yields: Ex Et+Ey Eu=Et 2 cosθ+Eu 2 cosθ=(And 2 +Eu 2 )cosθ; Ey Et-Ex Eu=Et2sinθ+Eu2sinθ=(Et 2 +Eu 2 )sinθ; Then we can get: cosθ=(Ex Et+Ey Eu) / (Et 2 +Eu 2 ); sinθ=(Ey Et-Ex Eu) / (Et 2 +Eu 2 ); The origin of the Cartesian coordinate system of the touch screen is (Ox, Oy), where 0x = Ax - (At cosθ – Au sinθ) and Oy = Ay - (At sinθ - Av cosθ). Based on the origin coordinates, coordinate transformation formula, specific values ​​of cosθ and sinθ of the detection platform's Cartesian coordinate system, the position of the touchable area in the Cartesian coordinate system of the detection platform is calculated.

3. The touchscreen linearity testing method according to claim 2, characterized in that, Based on the position of the touchable area in the Cartesian coordinate system of the detection platform, a linearity detection path is planned, including: Calculate the coordinates of the four vertex pixels of the touchable area in the Cartesian coordinate system of the detection platform plane; Choose any two of the four vertex pixels as the start and end points of the linearity detection path.

4. The touchscreen linearity testing method according to claim 3, characterized in that, The linearity detection path includes a first detection route, a second detection route, a third detection route, and a fourth detection route: The first detection route is parallel to the third detection route, and the second detection route intersects with the fourth detection route: the end point of the first detection route is the start point of the second detection route, and the end point of the second detection route is the start point of the third detection route. The end point of the third detection route is the starting point of the fourth detection route, and the end point of the fourth detection route is the starting point of the first detection route.

5. The touchscreen linearity testing method according to claim 4, characterized in that, Several test pixels are set along the linearity detection path; The test checks whether the deviation between the actual coordinates of the test pixel and the linearity detection path exceeds a preset allowable value; if so, an alarm is triggered and the test ends.

6. The touchscreen linearity testing method according to claim 1, characterized in that, Place the touchscreen on the inspection platform and construct a Cartesian coordinate system for the inspection platform, including: Place the touchscreen on the testing platform with the screen facing away from the surface of the testing platform; The first side of the detection platform is taken as the X-axis, the second side perpendicular to the first side is taken as the Y-axis, and the point where the first side and the second side intersect is taken as the origin of the coordinate system.

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