KR20120074373A - Method and device for inspecting touchscreen - Google Patents

Abstract

The present invention relates to a touch screen inspection method and apparatus. In the touch screen inspection method according to an embodiment of the present invention, selecting at least one of the one or more patterns stored in the memory, moving the conductive bar in contact with the surface of the touch screen according to the selected pattern, the conductive bar Comparing the input information generated in the touch screen with the selected pattern, and inspecting the touch screen based on the comparison result. According to the method, it is possible to efficiently inspect whether the touch screen is defective by checking coordinate accuracy and linearity while minimizing damage to the touch screen.

Description

METHOD AND DEVICE FOR INSPECTING TOUCHSCREEN}

The present invention relates to a method and apparatus for inspecting a touch screen, and more particularly, to a method and apparatus for conveniently and quickly inspecting coordinate accuracy and linearity of a capacitive touch screen.

The touch screen is an input device that detects a touch of a user's finger or other input object and converts it into a suitable electric signal to recognize coordinates or gestures, and is applied to various electronic devices. In particular, since the touch screen is directly coupled to the display device of the electronic device, it can replace a space occupied by a separate input device such as a keypad, and thus is widely applied to an electronic device such as a mobile phone, a smartphone, a PDA, a tablet PC, and the like.

The touch screen may be classified into a resistive type, a capacitive type, an ultrasonic type, and an infrared type according to a method of detecting a touch input. Among these, the capacitive method detects the position of a contact object by using a change in capacitance generated between the contacted object and the transparent sensing electrode when an electrically conductive object (EX> finger) is touched. . Capacitive touch screens have the advantages of longer life, thinner thickness, and easier multi-touch support than other touch screens.

The capacitive touch screen is configured to form a sensing electrode with a transparent conductive material such as ITO, IZO, ZnO, carbon nanotube, etc. on a transparent substrate, and electrically connects the touch sensor chip including a sensing circuit to determine a contact input. It is made by connecting. Before the touch screen is mounted on the electronic device, it is necessary to undergo an inspection process. The capacitive touch screen is inspected by a conductive bar having electrical conductivity.

Unlike resistive touch screens in which a touch input is recognized only when a constant pressure is applied, a capacitive touch screen can recognize a minute contact of a conductive bar as an input. Rather, as an existing inspection device that applies pressure above a certain strength to the capacitive touch screen, defects such as scratches or the like occur on the surface of the touch screen due to air bubbles in the protective film attached to the surface of the touch screen during the inspection step. This may cause problems such as a decrease in inspection accuracy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a touch screen inspection method and apparatus capable of quickly and accurately inspecting a coordinate recognition degree of a touch screen without causing a defect such as a scratch on the surface of the touch screen to be inspected. do.

In order to achieve the above object, according to an embodiment of the present invention, the step of selecting at least one of the one or more patterns stored in the memory, moving the conductive bar in contact with the touch screen surface according to the selected pattern, the conductive A touch screen inspection method is provided, comprising comparing input information generated in the touch screen by a bar with the selected pattern, and inspecting the touch screen based on the comparison result.

In addition, according to another embodiment of the present invention, a memory unit, a tray including a platform on which one or more touch screens can be mounted, a direction in contact with a surface of the touch screen seated on the platform and perpendicular to the touch screen surface And a control unit configured to move the conductive bar by selecting at least one of patterns stored in the memory unit, wherein the control unit is configured to be generated in the touch screen as the conductive bar moves. A touch screen inspection device for inspecting the touch screen by comparing input information with the selected pattern is provided.

According to the present invention, it is possible to inspect whether the touch screen is defective quickly and accurately without generating a defect such as scratch on the surface of the touch screen.

1 is a block diagram briefly showing an internal structure of a touch screen inspection device according to an embodiment of the present invention;
2 is a flowchart provided to explain a touch screen inspection method according to an embodiment of the present invention;
3 is a view showing briefly the inspection unit of the touch screen inspection apparatus according to an embodiment of the present invention,
4 to 6 are operation diagrams provided to explain a touch screen inspection method according to an embodiment of the present invention.

DETAILED DESCRIPTION The following detailed description of the invention refers to the accompanying drawings that show, by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention are different but need not be mutually exclusive. For example, certain features, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in connection with an embodiment. It is also to be understood that the position or arrangement of the individual components within each disclosed embodiment may be varied without departing from the spirit and scope of the invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention, if properly described, is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled. Like reference numerals in the drawings refer to the same or similar functions throughout the several aspects.

DETAILED DESCRIPTION Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention.

1 is a block diagram briefly illustrating an internal structure of a touch screen inspection apparatus according to an embodiment of the present invention.

Referring to FIG. 1, the touch screen inspection apparatus 100 according to the present exemplary embodiment includes a control unit 110, an inspection unit 120, a platform 130, a memory 140, and a display unit 150.

The touch screen to be examined is placed on one or more touch screen seating portions provided on the platform 130. At least one small sized air hole is provided in the seating portion so that the touch screen placed on the seating portion does not escape or flow during the inspection process. When the touch screen is placed on the seating portion, the touch screen may be brought into close contact with the seating portion by sucking air through the air hole, thereby preventing the flow and departure of the touch screen that may occur during the inspection process.

The platform 130 may be provided with a circuit board connected to the touch sensor chip of the touch screen. The circuit board may be provided for each touch screen seating part provided in the platform 130, and the controller 150 receives coordinate information generated on the touch screen through the circuit board.

The inspection unit 120 includes a conductive bar for inputting coordinate information on a touch screen placed on the seating part of the platform 130, and moves the conductive bar according to a command transmitted from the controller 110. The controller 150 selects at least one of predetermined pattern information stored in the memory 140 to inspect the touch screen, and transmits the selected pattern information to the inspection unit 120. When the inspection unit 120 contacts the conductive bar with the touch screen and moves the conductive bar according to the selected pattern information, the controller 150 determines whether the touch screen is defective by comparing coordinate information generated on the touch screen with the pattern information. Can be.

The touch screen inspection process may be confirmed through the display unit 150. The display unit 150 may display the pattern information selected by the controller 110 and the coordinate information generated on the test target touch screen, and display the test result in the form of a table or a graph. In one embodiment, the controller 110 is a memory 140 in the form of a computer-readable file of the comparison result between the coordinate information and the pattern information extracted from the test target touch screen so that the user can efficiently manage the test results of the touch screen ) Can be stored.

2 is a flowchart provided to explain a touch screen inspection method according to an embodiment of the present invention.

Referring to FIG. 2, in the touch screen inspection method according to the present embodiment, the touch screen to be inspected is mounted on the platform 130 (S200). The platform 130 may include at least one air hole for fixing the seated touch screen so as not to move in the inspection process. By sucking air through the air hole, the touch screen mounted on the platform can be fixed without flow during the inspection process.

Meanwhile, the platform 130 includes a circuit board electrically connected to the touch sensor chip included in the touch screen. In one embodiment, the touch screen is manufactured by attaching a panel provided with a sensing electrode and a wiring pattern, and an FPCB mounted with a touch sensor chip to each other by an ACF process. The circuit board included in the platform 130 is connected to the FPCB on which the touch sensor chip is mounted by a connector, and the controller 110 may receive coordinate information generated by the touch sensor chip through the circuit board. .

When the touch screen to be inspected is seated on the platform 130, the controller 110 selects at least one of the test patterns stored in the memory 140 (S210). In one embodiment, the control unit 110 is a test pattern for evaluating the coordinate linearity of the touch screen, the contact is continuously applied in the effective input area of the touch screen, such as N-shaped pattern, X-shaped pattern, L-shaped pattern, etc. One of the patterns can be selected.

Alternatively, in order to measure simple coordinate accuracy of the touch screen, a pattern for applying multiple inputs to the same position may be selected. For example, the effective input area of the touch screen may be divided into an M × N matrix, and the touch screen may be inspected by calculating a coordinate error of the corresponding input while repeatedly applying an input to the center points of the divided areas.

The touch screen inspection form according to each pattern selected by the controller 110 will be described later with reference to FIGS. 4 and 5.

When selection of the test pattern is completed, the controller 110 contacts the conductive bar included in the test unit 120 to the touch screen surface and moves the conductive bar according to the selected pattern (S220). In the case of the capacitive touch screen, since the coordinate of the contact input is determined based on the capacitance change formed between the conductive contact object and the sensing electrode, not the pressure of the contact object, the conductive bar should be used for the inspection.

In this case, since the inspection process according to the present invention is typically performed before the product shipping step, a predetermined protective film may be attached to the surface of the touch screen to be inspected. Therefore, when the conductive bar exerts more pressure than necessary on the surface of the touch screen (exactly, the surface of the protective film), the protective film is broken and scratches are generated on the surface of the touch screen, or by bubbles generated in the process of attaching the protective film. The touch screen may be damaged.

Therefore, in the present invention, in order to solve the above problems, the inspection process proceeds to the conductive rod having a fluidity in the direction perpendicular to the touch screen surface. A description with reference to FIG. 3 is as follows.

Referring to FIG. 3, the conductive rod 310 included in the inspection unit 120 is connected to a weight 320 having a predetermined weight and is inserted into a hole provided in a separate seating unit 330. The diameter of the hole corresponds to the outer diameter of the conductive rod 310. Although the conductive rod 310 and the weight 320 are fixed so as not to move with each other, the weight 320 is not fixed to the upper surface of the seating portion 330 and simply lies, so the conductive rod 310 is shown in FIG. 3. It has a certain distance of fluidity in the direction of the arrow shown. A conductive tape or protective tape 340 may be attached to a surface of the conductive bar 310 that contacts the touch screen 350 or the protective film 360 thereon.

As described above, a predetermined protective film 360 may be attached to the touch screen 350 to be inspected. In this process, bubbles are generated between the touch screen 350 and the protective film 360, such that the curved surface 370. ) May be generated. In the present embodiment, since the conductive bar 310 has fluidity in a direction perpendicular to the surface of the touch screen 350 while moving, the weight 320 connected to the conductive bar 310 is seated on the curved surface 370. It is naturally spaced apart from the portion 330 instantaneously, and after passing through the curved surface 370, the weight 320 again falls to contact the seating portion 330 by gravity. Therefore, even when the touch screen 350 in which the curved surface 370 is generated due to air bubbles or the like can be inspected without damage, the curved touch screen (Contour Touchscreen) to be mounted on the curved display can also be inspected without any other equipment replacement.

The controller 110 acquires input information generated in the touch screen by the conductive bar in contact with the surface of the touch screen (S230). The input information includes coordinate information determined by the contact of the conductive bar in the touch sensor chip of the touch screen, and if the test pattern selected by the controller 110 in step S210 is a pattern for testing the linearity of the touch screen, continuous Coordinate information can be obtained in a form similar to the selected test pattern.

The controller 110 compares the test pattern selected in step S210 with the input information acquired from the touch screen in step S230 (S240). A description with reference to FIGS. 4 and 5 is as follows.

When the touch screen is seated on the platform 130, the controller 110 obtains information of the touch screen to be inspected by selecting a model name of the touch screen to be inspected or directly inputting a specification of the touch screen to be inspected. The controller 110 determines how to actually contact and move the conductive bar on the surface of the touch screen to be inspected according to the inspection pattern selected in step S210 based on the information. For example, in the case of a 3.5-inch touch screen and a 7-inch touch screen, even if the same test pattern is selected, the paths for contacting and moving the conductive bars should be determined differently.

When the N-shaped pattern is selected as the test pattern as shown in FIG. 4, the controller 110 moves the conductive bar in contact with the touch screen surface to the N-shaped. In this case, assuming that the inspection is terminated at the upper left portion of the N-shaped pattern starting from the lower left portion, it is possible to define a one-time inspection to move from the lower left portion to the upper right portion without the contact of the conductive bar being released. Do.

When the conductive bar completes movement in the shape of the selected test pattern, the controller 110 obtains input information generated on the touch screen according to the movement of the conductive bar. The controller 110 obtains input information actually generated on the touch screen by the movement of the conductive bar, regardless of the selected test pattern. In general, the actual input information generated in the touch screen may have a form similar to the selected test pattern.

Alternatively, as illustrated in FIG. 5, the touch screen may be divided into a matrix structure having M × N input regions, and the conductive bars may be sequentially contacted several times in each region. In this case, the test pattern selected by the controller 110 may be coordinate information corresponding to the center of each input area, and M x N coordinate information generated on the touch screen by contact of the conductive bar is compared with the test pattern.

In one embodiment, the controller 110 may compare the selected test pattern with the coordinates of the input information received from the touch screen. In the case of FIG. 4, the N-shaped pattern is compared with the pattern information including coordinate information for each sampling period on the touch screen. In FIG. 5, the coordinate information of each of the M x N regions included in the selected test pattern is compared with the M x N coordinate information generated on the touch screen. In this case, in order to increase the reliability of the test, the conductive bars may be contacted to the M × N input areas n times each time, and the average coordinate may be calculated for each input area and compared with the center coordinate information included in the test pattern.

The controller 110 determines whether the touch screen is defective based on the comparison result obtained in step S240 (S250). For example, if the N-shaped pattern is selected as the test pattern of FIG. 4, the linearity of the input information acquired from the touch screen may be used as a criterion for determining whether the touch screen is defective.

In the N-shaped pattern consisting of five straight lines, the linearity of the touch screen may be determined depending on how much error occurs in the coordinates of the direction crossing the progress direction of each conductive bar. That is, in the case of the first straight line input starting from the bottom left and proceeding in the Y axis + direction, it is ideal that the X axis direction coordinate of the touch screen is fixed to one value while the conductive bar is moving. Therefore, by calculating how much the coordinates of the direction crossing the conductive bar crosses the direction of change, and comparing the calculated change amount with the reference coordinates of the inspection pattern selected by the controller 110 to determine whether the touch screen is defective according to the magnitude of the error. You can decide.

In the case of FIG. 5 in which the effective input area of the touch screen is divided into M x N input areas and the conductive bar is contacted with each input area n times, the control unit 110 calculates an average value of n coordinates generated in each contact area. ) May be compared with reference coordinates of the selected test pattern, and it may be determined whether the touch screen is defective according to the magnitude of the error.

Referring to the case of the X-shaped pattern shown in Figure 6, it is possible to determine whether the touch screen is defective by using the slope defined by the ratio of the amount of change in the X-axis direction and the amount of change in the Y-axis direction. Unlike the N-shaped pattern, the X-shaped pattern is an effective pattern for evaluating the input linearity of the touch screen in the diagonal direction. Therefore, when the X-shaped pattern is selected, it may be more efficient to compare the X-axis direction coordinates and the Y-axis direction coordinates based on the slope than to calculate and compare the X-axis direction coordinates separately.

The touch sensor chip included in the touch screen obtains coordinate information from the touch screen at regular sampling periods. Therefore, the controller 110 of the test apparatus 100 also calculates a tilt using input information acquired from the touch screen at regular intervals, and tilts the selected test pattern (for example, in the case of an X-shaped pattern, one moving direction). The slope is constant). The controller 110 may calculate an error of the slope according to the comparison result, and determine whether the touch screen is defective.

The present invention has been described above with reference to specific embodiments of the present invention, but this is only illustrative and does not limit the scope of the present invention. Those skilled in the art can change or modify the described embodiments without departing from the scope of the present invention. Each of the functional blocks or means described herein may be implemented by various well-known elements such as an electronic circuit, an integrated circuit, an application specific integrated circuit (ASIC), and the like. Can be. Components such as means described as separate in the specification and claims may be simply functionally distinct and may be physically implemented as one means, and components such as means described as a single element may be It can be made in combination. In addition, each method step described herein may be changed in order without departing from the scope of the present invention, and other steps may be added. In addition, the various embodiments described herein may be implemented independently as well as each other as appropriate. Therefore, the scope of the invention should be defined by the appended claims and their equivalents, rather than by the described embodiments.

100: inspection device
110:
120: inspection unit
130: platform
140: memory
150: display unit

Claims (19)

In the method of testing the touch screen,
Selecting at least one of one or more patterns stored in memory;
Contacting and moving the conductive bar to the touch screen surface according to the selected pattern;
Comparing input information generated in the touch screen by the conductive bar with the selected pattern; And
Inspecting the touch screen based on the comparison result; Touch screen inspection method comprising a. The method of claim 1,
And wherein the pattern is a pattern for checking input linearity of the touch screen. The method of claim 2,
And wherein the pattern comprises at least one of an N-type, an X-type, and a R-type pattern. The method of claim 1, wherein the comparing step,
And comparing the coordinate information included in the input information with the coordinates of the selected pattern. The method of claim 4, wherein the inspecting step,
And determining that the touch screen is defective when at least some of the coordinate information is out of a predetermined range from the coordinates of the selected pattern. The method of claim 4, wherein
And comparing the coordinate information corresponding to a direction in which the conductive bar crosses a moving main direction with the coordinates of the selected pattern. The method of claim 4, wherein
And a slope of a direction in which the conductive bar moves to a slope of a coordinate of the selected pattern. The method of claim 5,
Setting the range to a value input by a user; Touch screen inspection method comprising a. Touch screen inspection method. The method of claim 1,
The touch screen is a touch screen inspection method, characterized in that the capacitive touch screen. The method of claim 7, wherein the moving step,
And moving the conductive bar, which is movable in a direction perpendicular to the touch screen surface, in contact with the touch screen surface. A memory unit;
A tray comprising a platform on which one or more touchscreens can be seated;
An inspection unit in contact with a surface of the touch screen mounted on the platform and including a conductive bar movable in a direction perpendicular to the touch screen surface; And
A controller configured to move the conductive bar by selecting at least one of patterns stored in the memory unit; Including,
The control unit inspects the touch screen by comparing the input pattern generated in the touch screen with the selected pattern as the conductive bar moves. The method of claim 11, wherein
And the pattern is a pattern for checking input linearity of the touch screen. The method of claim 12,
The pattern is a touch screen inspection device, characterized in that it comprises at least one of the N-shape, X-shape, and L-shaped pattern. The method of claim 11, wherein the control unit,
And a coordinate of the selected pattern and coordinate information included in the input information. 15. The apparatus of claim 14,
And determining that the touch screen is defective when at least some of the coordinate information is out of a predetermined range from the coordinates of the selected pattern. 15. The apparatus of claim 14,
And comparing the coordinate information corresponding to a direction crossing the main direction in which the conductive bar moves with the coordinates of the selected pattern. 15. The apparatus of claim 14,
And a slope of a direction in which the conductive bar moves to a slope of a coordinate of the selected pattern. The method of claim 11, wherein the inspection unit,
A weight having a predetermined weight and whose outer diameter is larger than the outer diameter of the conductive rod; And
A seating part having a hole into which the conductive bar is inserted; Including,
And the weight is physically connected to the conductive bar so that the conductive bar does not penetrate the hole of the seating portion, and is placed on an upper surface of the seating portion. The method of claim 11, wherein the inspection unit,
A protective tape attached to a surface of the conductive bar in contact with the surface of the touch screen; Touch screen inspection apparatus comprising a.

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