KR20140057980A - Method and apparatus for inspecting defect of touch panel - Google Patents

Abstract

The present invention provides an inspecting method and an inspecting apparatus of a defect for a touch panel, which can be used to inspect whether a short circuit occurs in the touch panel. According to an embodiment of the present invention, the inspecting apparatus of a defect for the touch panel comprises a stage on which the touch panel is mounted; a touch panel driving circuit which supplies a driving pulse to Tx lines of the touch panel and which converts outputs of the sensor nodes received through Rx lines to digital data to output touch raw data; and a haberdashery determination unit which analyzes the touch raw data to inspect whether a short circuit occurs in the touch panel.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of inspecting a touch panel,

The present invention relates to a defect inspection method and an inspection apparatus of a touch panel capable of inspecting whether or not a touch panel is short-circuited.

A user interface (UI) enables communication between a person (user) and various electric or electronic devices, allowing a user to easily control the device as desired. Representative examples of such a user interface include a keypad, a keyboard, a mouse, an on screen display (OSD), a remote controller having infrared communication or radio frequency (RF) communication function, and the like. User interface technology has been developed to enhance the user's sensibility and ease of operation. Recently, the user interface has evolved into a touch UI, a voice recognition UI, a 3D UI, and the like.

Touch UI is becoming a necessity for portable information devices and is being applied to household appliances. As an example of a touch screen device for implementing a touch UI, a mutual capacitance type touch screen device capable of sensing proximity or sensing multi-touch (or proximity) as well as a touch is attracting attention.

The mutual capacitive touch screen device includes a touch panel having Tx lines, Rx lines intersecting Tx lines, and sensor nodes formed at intersections of Tx lines and Rx lines. Each of the sensor nodes has mutual capacity. The touch screen device senses a change in the voltage charged in the sensor nodes before and after the touch (or proximity) to determine whether or not the conductive material is in contact (or proximity) and its position. The touch screen device supplies drive pulses to the Tx lines of the touch panel, converts the outputs of the sensor nodes received through the Rx lines into touch row data, which is digital data, and analyzes the touch row data through the touch controller, Respectively.

On the other hand, when a short circuit occurs between the Tx lines of the touch panel, since short-circuited Tx lines are connected to more sensor nodes than other Tx lines, the output of the sensor nodes received through the Rx lines in the shortened Tx lines There is a problem in that it becomes large. Also, when a short circuit occurs between the Rx lines of the touch panel, there is a problem that the outputs of the sensor nodes received through the short-circuited Rx lines become equal to each other. That is, when a short circuit occurs between the Tx lines of the touch panel or between the Rx lines, the touch screen device can not operate normally. However, there is a disadvantage that it is difficult to detect short-circuit between the Tx lines of the touch panel and short-circuit between the Rx lines before the product is completed and tested.

The present invention provides a defect inspection method and an inspection apparatus for a touch panel capable of inspecting a defect of a touch panel.

According to an embodiment of the present invention, there is provided a method of inspecting a touch panel defect, comprising: supplying driving pulses to Tx lines of a touch panel; converting output of sensor nodes received through Rx lines to digital data to obtain touch row data; Calculating filter data by applying a first filter to the touch row data; Calculating a representative value of the number of filter data having a value larger than a first threshold value for each Tx line; And determining that the touch panel is a defective product if the case where the representative value has a value larger than the second threshold value is calculated.

A method for inspecting a touch panel defect according to another embodiment of the present invention includes supplying driving pulses to Tx lines of a touch panel and converting outputs of sensor nodes received through Rx lines to digital data to obtain touch row data step; calculating sum of the touch row data for each Rx line by summing the touch row data of i (i is a natural number) frame period for each Rx line; Calculating a number of cases in which the sum of the touch row data of one Rx line is equal to the sum of the touch row data of the neighboring Rx lines during the N frame period as a representative value of the one Rx line; And determining that the touch panel is a defective product when a case where the sum of the representative values of the Rx lines is equal to or greater than a third threshold value is calculated.

A touch panel failure inspection apparatus according to an embodiment of the present invention includes a stage on which the touch panel is seated; A touch panel driving circuit for supplying drive pulses to the Tx lines of the touch panel, converting the outputs of the sensor nodes received through the Rx lines to digital data and outputting touch row data; And a good part determiner for analyzing the touch row data and checking whether the touch panel is short-circuited.

The present invention applies a first filter including a differential filter to the touch row data to calculate filter data and then determines whether the number of filter data having a value larger than the first threshold value is greater than a second threshold value , And whether or not the touch panel is short-circuited. Further, the present invention is characterized in that the second filter including the differential filter is applied to the touch row data to calculate the differential value data, and then the number of differential value data having a value of "0 & It is possible to check whether or not the touch panel is short-circuited by determining whether the value is greater than the third threshold value. That is, according to the present invention, whether or not the touch panel is short-circuited can be inspected with an easy method, and the defect of the touch panel can be inspected. Therefore, according to the present invention, it is possible to increase the number of sampling inspections or the total number of inspections of whether or not the touch panel is short-circuited, thereby reducing shipment of the bad touch panel.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is an exemplary schematic illustration of a touch screen device.
2 is a flowchart showing a touch panel defect inspection method according to a first embodiment of the present invention.
3A is an exemplary illustration showing touch row data when a short line occurs between Tx lines;
Figure 3b is an example showing filter data.
4 is a flowchart showing a touch panel defect inspection method according to a second embodiment of the present invention.
FIG. 5A is an exemplary view showing touch row data when a short line occurs between Rx lines; FIG.
5B is an exemplary view showing differential value data;
5C is a graph showing the case where the differential value data is "0 ".
FIG. 5D is a histogram showing the number of times when the differential value data is "0" during a plurality of frame periods. FIG.
6 is a block diagram showing a touch panel defect inspection apparatus according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Like reference numerals throughout the specification denote substantially identical components. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 is an exemplary schematic diagram of a touch screen device. Referring to FIG. 1, the touch screen device includes a touch panel 10, a touch panel driving circuit 20, and a touch controller 30.

The touch panel 10 includes Rx lines (R1 to Rm, m being a natural number of 2 or more) intersecting Tx lines (T1 to Tn, n is a natural number of 2 or more), Tx lines (T1 to Tn) And m x n sensor nodes formed at the intersections of the Rx lines R1 to Rm. It should be noted that each of the sensor nodes may be implemented as mutual capacitance in an equivalent circuit, but is not limited thereto.

When the touch screen device is combined with the display device, the touch panel 10 may be bonded to the upper portion of the display panel of the display device. In particular, when the display device is implemented as a liquid crystal display device, the touch panel 10 may be bonded onto the upper polarizer plate of the display panel of the liquid crystal display device, or may be bonded between the upper polarizer plate and the upper substrate of the display panel. In addition, the sensor nodes of the touch panel 10 may be formed on the lower substrate together with the pixel array (in-cell type) in the display panel of the liquid crystal display device.

The touch panel driving circuit 20 supplies driving pulses to the Tx lines T1 to Tn and senses the sensor node voltage through the Rx lines R1 to Rm in synchronization with the driving pulse. The touch panel drive circuit 20 includes a Tx drive circuit 21 and an Rx drive circuit 22. The Tx driving circuit 21 and the Rx driving circuit 22 can be integrated in one ROIC (Read-out IC).

The Tx drive circuit 21 selects a Tx channel to output a drive pulse under the control of the touch controller 30 and supplies drive pulses to Tx lines connected to the selected Tx channel. The Rx driving circuit 22 selects an Rx channel to receive the voltage of the sensor nodes under the control of the touch controller 30 and receives the voltage of the sensor nodes through the Rx lines connected to the selected Rx channel. The Rx driving circuit 22 samples the voltage of the sensor node received through the Rx lines R1 to Rm and accumulates the voltage in the integrator. The Rx driving circuit 22 inputs the voltage accumulated in the integrator to an analog-to-digital converter (ADC) and converts it into touch raw data (TRD), which is digital data, and outputs it.

The touch controller 30 includes a Tx setup signal for setting a Tx channel to which a drive pulse is to be output from the Tx drive circuit 21 and a Rx setup signal for setting an Rx channel to receive the sensor node voltage from the Rx drive circuit 22, Signal. Further, the touch controller 30 generates timing control signals for controlling the operation timing of the Tx driving circuit 21 and the Rx driving circuit 22.

The touch controller 30 includes a touch coordinate calculation unit. The touch coordinate calculator compares the touch row data TRD input from the Rx driver circuit 22 with a predetermined threshold value and determines touch row data TRD equal to or larger than a predetermined threshold value as touch (or proximity) input data On the other hand, the touch row data TRD lower than the predetermined threshold value is judged as data having no touch (or proximity) input. The touch coordinate calculation unit executes a preset touch coordinate calculation algorithm to calculate coordinates for each of the touch row data TRD determined as touch (or proximity) input data, and outputs touch recognition result data (HIDxy) including coordinate information Output. The touch coordinate calculation algorithm can be implemented by any known algorithm. The touch coordinate calculation unit may be implemented by an MCU (Micro Controller Unit).

On the other hand, when a short circuit occurs between the Tx lines T1 to Tn of the touch panel 10 of the touch screen device, the short-circuited Tx lines are connected to more sensor nodes than the other Tx lines, There is a problem in that the output of the sensor nodes received through the Rx lines becomes large. Further, when a short circuit occurs between the Rx lines R1 to Rm of the touch panel, there is a problem that the outputs of the sensor nodes received through the short-circuited Rx lines become equal to each other. That is, when a short circuit occurs between the Tx lines Tl through Tn of the touch panel or a short circuit occurs between the Rx lines Rl through Rm, there arises a problem that the touch screen device miscodes the touch coordinates. That is, there arises a problem that the touch screen device can not normally operate. Hereinafter, an inspection method capable of checking whether or not the touch panel is short-circuited by attaching FIGS. 2, 3A, 3B, 4, 5A to 5D will be described in detail.

2 is a flowchart illustrating a touch panel defect inspection method according to a first embodiment of the present invention. FIG. 2 shows a method of inspecting a touch panel defect, which determines that the touch panel 10 is a defective product when a short circuit occurs between the Tx lines T1 to Tn of the touch panel 10. FIG. Referring to FIG. 2, the touch panel defect inspection method includes first through fourth steps (S101 through S106).

First, a first step S101 is to supply drive pulses to the Tx lines T1 to Tn of the touch panel 10 and output the outputs of the sensor nodes received through the Rx lines R1 to Rm to a digital And acquires the touch row data (TRD).

FIG. 3A is an exemplary diagram showing touch row data when a short line occurs between Tx lines. FIG. FIG. 3A shows the touch row data TRD for one frame period. The x-axis represents the position of the Rx line, the y-axis represents the position of the Tx line, and the z-axis represents the size of the touch row data TRD. Referring to "A" shown in FIG. 3A, since the Tx lines (T1 to Tn) are arranged in the x-axis direction, it is possible to see that the touch row data (TRD) . This is because, when a short circuit occurs between the Tx lines T1 to Tn of the touch panel 10, the short-circuited Tx lines are connected to more sensor nodes than the other Tx lines, The output of the sensor nodes received through the sensor node becomes larger. (S101)

Secondly, in the second step S102, the first filter F1 is applied to the touch row data TRD of one frame period to calculate filter data. In Fig. 3A, when a short circuit occurs between the Tx lines, the touch row data TRD appears at a point on the y-axis, which is the position of the short-circuited Tx lines. The first filter F1 may be implemented as a differential filter applied in the y-axis direction. The differential filter is also known as a sharpness filter. When the first filter F1 is implemented as a differential filter, since the filter data is calculated by amplifying the difference between any touch row data and neighboring touch row data in the y-axis direction by an amplification constant, Quot; B "in Fig. 3B. 3B is an exemplary diagram showing filter data. In FIG. 3B, filter data FD of one frame period is shown. The x-axis represents the position of the Rx line, the y-axis represents the position of the Tx line, and the z-axis represents the size of the filter data FD.

On the other hand, the first filter F1 can be defined as Equation (1).

Alternatively, the first filter F1 may be defined as Equation (2).

The first filter F1 may include not only a differential filter applied in the y-axis direction but also an average filter applied in the x-axis direction. The average filter is also known as a smoothing filter. Specifically, the first filter F1 can be defined as Equation (3).

Alternatively, the first filter F1 may be defined as shown in Equation (4).

In Equations (1) to (4),? Means an amplification constant.

When the first filter F1 includes an average filter as shown in Equation 3 and Equation 4, the filter data FD is calculated by averaging any touch row data and touch row data neighboring in the x-axis direction, The filter data FD is expressed by being flattened in the x-axis direction.

Meanwhile, in the second step S102, the differential filter of the first filter F1 is applied in the y-axis direction and the average filter is applied in the x-axis direction. However, it should be noted that the present invention is not limited thereto. That is, if necessary, the differential filter of the first filter F1 may be applied in the x-axis direction and the averaging filter may be applied in the y-axis direction. In the second step S102, the differential filter of the first filter F1 may be applied to both the x-axis direction and the y-axis direction, and the average filter may be applied to both the x-axis direction and the y-axis direction. (S102)

Thirdly, in a third step S103, a representative value, which is the number of filter data FD having a value larger than the first threshold value for each Tx line, is calculated. Specifically, referring to Equation (5), the third step (S103) is performed when the filter data FD (j, k) at the coordinates (j, k) has a value larger than the first threshold value TH1 1 "is assigned to the comparison value C (j, k) in the (j, k) In the third step S103, if the filter data FD (j, k) at the coordinates (j, k) has a large value equal to or smaller than the first threshold value TH1, (C (j, k)). The first threshold value TH1 may be preset to an appropriate value through a preliminary experiment.

Then, in the third step S103, a comparison value (k) of the kth Tx line is calculated as a representative value Inspection (k) of the line Tx (k is a natural number satisfying 1? K? N) C (j, k)) (j is a natural number satisfying 1? J? M). j denotes an x coordinate value, and k denotes a y coordinate value.

In the fourth step S104, S105, and S106, if there is a representative value having a value larger than the second threshold value among the representative values calculated for each Tx line, the touch panel 10 is determined as a defective product. Specifically, in the fourth step S104, S105, and S106, a representative value having a value larger than the second threshold value among the representative values (Inspection (1) to Inspection (n)) of the first to n- , It is determined that the touch panel 10 is a defective product. If there is no representative value having a value larger than the second threshold value among the representative values (Inspection (1) to Inspection (n)) of the first to nth Tx lines in the fourth step (S104, S105, It is determined that the touch panel 10 is good. The second threshold value can be preset to an appropriate value through a preliminary experiment. (S104, S105, S106)

As described above, according to the present invention, the first filter F1 including the differential filter is applied to the touch row data TRD to calculate the filter data FD, and then the value is larger than the first threshold value TH1 It is possible to check whether or not the touch panel is short-circuited by judging whether or not the number of filter data FD possessed by the touch panel is larger than the second threshold value. That is, according to the present invention, whether or not the touch panel is short-circuited can be inspected with an easy method, and the defect of the touch panel can be inspected.

4 is a flowchart illustrating a touch panel defect inspection method according to a second embodiment of the present invention. FIG. 4 shows a method of inspecting the touch panel 10 for determining that the touch panel 10 is a defective product when a short circuit occurs between the Rx lines R1 to Rm of the touch panel 10. Referring to FIG. 4, the touch panel defect inspection method includes first through fourth steps.

First, the first step S201 is to supply drive pulses to the Tx lines T1 to Tn of the touch panel 10 and output the outputs of the sensor nodes received through the Rx lines R1 to Rm to the digital And acquires the touch row data (TRD).

FIG. 5A is an exemplary diagram showing touch row data when a short line occurs between Rx lines. FIG. 5A shows the touch row data TRD for one frame period. The x-axis represents the position of the Rx line, the y-axis represents the position of the Tx line, and the z-axis represents the size of the touch row data TRD. When a short circuit occurs between the Rx lines R1 to Rm of the touch panel, the outputs of the sensor nodes received through the shorted Rx lines are equal to each other. (S201)

Second, in the second step S202, the touch row data TRDi of the i-th (i is a natural number) frame period is summed for each Rx line to calculate the sum of the touch row data for each Rx line. Specifically, the second step S202 calculates the touch row data sum RSi (j) of the jth line by summing the touch row data of the jth vertical line as shown in Equation (7).

Thirdly, in the third step S203, the number of cases in which the sum of the touch row data of one Rx line is equal to the sum of the touch row data of the neighboring Rx lines during the N frame period is set to a representative value . Specifically, in the third step S203, the second filter F2 is applied to the sum of the touch row data calculated for each Rx line to calculate the differential value data for each Rx line. The second filter F2 may be implemented as a differential filter. Accordingly, the second filter F2 can be defined as Equation (1) or Equation (2). That is, in the third step S203, the sum of the touch row data calculated for each Rx line is differentiated to calculate the differential value data for each Rx line. The third step S203 may calculate the differential value data Ti (j) of the jth Rx line by differentiating the sum RSi (j) of the touch row data of the jth Rx line.

5B is an exemplary diagram showing differential value data. Referring to FIG. 5B, the x-axis indicates the position (j) of the Rx line, and the y-axis indicates the differential value data. The differential value data Ti (j) of the jth Rx line means the slope value of the sum (RSi (j)) of the touch row data of the jth Rx line. Therefore, when the sum (RSi (j)) of the touch row data of the jth Rx line is equal to the sum of the touch row data of the Rx line neighboring the jj Rx line, the differential value data Ti ) Is calculated as "0 ".

Then, the third step S203 calculates the number of differential value data having a value of "0" for each Rx line as a representative value during the N frame period. Specifically, in the third step S203, when the differential value data Ti (j) of the j-th line has a value of 0 as in Equation (9), the number data Ti ' Quot; 1 ", otherwise, the number data Ti '(j) of the j-th line is assigned as "0 ".

5C is a graph showing the number data. Referring to FIG. 5C, the x-axis represents the position (j) of the Rx line, and the y-axis represents the value of the number data. As shown in FIG. 5C, the first to m-th pieces of data Ti '(1) to Ti' (m) during the i-th frame period have a value of "0" or "1".

In the third step S203, the sum of the number data of the j-th line is calculated as a representative value (RxShort (j)) of the j-th Rx line during the N frame period as shown in Equation (10).

FIG. 5D is a histogram showing the number (representative value) of differential value data having a value of "0 " during the N frame period. Referring to FIG. 5D, the x-axis denotes the position (j) of the Rx line, and the y-axis denotes the representative value.

On the other hand, in the third step S203, an average of the number of differential data having a value of "0" during the N frame period may be calculated as a representative value. (S203)

Fourth (S204, S205, and S206), the fourth step S204, S205, and S206 determine that the touch panel 10 is defective when the sum of the representative values of any one of the Rx lines is equal to or greater than the third threshold value. Specifically, in the fourth step S204, S205, and S206, a representative value having a value larger than the third threshold value among the representative values RxShort (1) to Rxshort (m) of the first to m- , It is determined that the touch panel 10 is a defective product. If there is no representative value having a value larger than the third threshold value among the representative values RxShort (1) to Rxshort (m) of the first to m-th Rx lines in the fourth step S204, S205, It is determined that the touch panel 10 is good. The third threshold value can be preset to an appropriate value through a preliminary experiment. (S104, S105, S106)

As described above, according to the present invention, the second filter (F2) including the differential filter is applied to the touch row data (TRD) to calculate the differential value data (T) It is possible to check whether or not the touch panel is short-circuited by calculating the number of differential value data as a representative value and judging whether the representative value is larger than the third threshold value. That is, according to the present invention, whether or not the touch panel is short-circuited can be inspected with an easy method, and the defect of the touch panel can be inspected.

6 is a block diagram showing a touch panel failure inspection apparatus according to an embodiment of the present invention. 6, a touch panel defect inspection apparatus according to an exemplary embodiment of the present invention includes a stage 100, a touch panel driving circuit 200, a touch controller 300, a good quality determination unit 400, a display device 500, And the like.

In the stage 100, the touch panel 110 to be inspected for a short circuit is loaded and seated. The touch panel defect inspection apparatus may further include a loading device for loading or unloading the touch panel 110 on the stage 100. That is, the touch panel 110 may be loaded on the stage 100 by the loading device, and then unloaded by the loading device when the inspection is completed.

After the touch panel 110 is mounted on the stage 100, the touch panel driving circuit 200 is connected to the touch panel 110. The touch panel driving circuit 200 supplies driving pulses to the Tx lines T1 to Tn and senses the sensor node voltage through the Rx lines R1 to Rm in synchronization with the driving pulse. The touch panel driving circuit 200 includes a Tx driving circuit 210 and an Rx driving circuit 220.

The Tx driving circuit 210 selects a Tx channel to output a driving pulse under the control of the touch controller 300 and supplies driving pulses to Tx lines connected to the selected Tx channel. The Rx driving circuit 220 selects an Rx channel to receive the voltage of the sensor nodes under the control of the touch controller 300 and receives the voltage of the sensor nodes through the Rx lines connected to the selected Rx channel. The Rx driving circuit 220 samples the voltage of the sensor node received through the Rx lines R1 to Rm and accumulates the voltage in the integrator. The Rx driving circuit 220 inputs the voltage accumulated in the integrator to the analog-to-digital converter (ADC) and converts it into touch row data (TRD), which is digital data, and outputs it.

The touch controller 300 includes a Tx setup signal for setting a Tx channel to which a driving pulse is to be output in the Tx driving circuit 210 and a Rx setup signal for setting an Rx channel for receiving a sensor node voltage in the Rx driving circuit 220. [ Signal. In addition, the touch controller 300 generates timing control signals for controlling the operation timings of the Tx driving circuit 210 and the Rx driving circuit 220.

The good product determination unit 400 receives the touch row data TRD from the Rx driving circuit 220. The good product judging unit 400 judges whether a short circuit has occurred between the Tx lines T1 to Tn of the touch panel 110 based on the touch panel defect inspection method according to the first embodiment of the present invention described with reference to FIG. It can be judged. In addition, the good product judging section 400 judges whether a short circuit occurs between the Rx lines R1 to Rm of the touch panel 110 based on the touch panel defect inspection method according to the second embodiment of the present invention described with reference to FIG. Can be determined. The good-quality judging unit 400 judges whether the touch panel defect inspection method according to the first embodiment of the present invention described with reference to FIG. 2 and the touch panel defect inspection method according to the second embodiment of the present invention It is possible to determine at a time whether a short circuit has occurred between the Tx lines T1 to Tn of the touch panel 110 and a short circuit has occurred between the Rx lines R1 to Rm.

The good product determination unit (400) outputs the good product determination signal (Si) indicating the touch panel failure inspection result to the display device (500). When the touch panel 110 is determined to be a defective product, the defective product determination unit 400 outputs a defective product determination signal Si indicating a defective product at a first logic level. If the touch panel 110 is determined to be good, the good product determination unit 400 outputs a good-quality determination signal Si of a second logic level indicating good products.

The display device 500 displays the touch panel short-circuit result according to the good-quality determination signal Si from the good-quality determination unit 400. For example, the display device 500 may display a letter "Good" or a green color when the good decision signal Si of the first logic level is input. The display device 500 may display a letter "defective" or red when the second logic level good-quality determination signal Si is input.

As described above, according to the present invention, a first filter including a differential filter is applied to touch row data to calculate filter data, and then the number of filter data having a value larger than the first threshold value is larger than a second threshold value It is possible to check whether or not the touch panel is short-circuited. Further, the present invention is characterized in that the second filter including the differential filter is applied to the touch row data to calculate the differential value data, and then the number of differential value data having a value of "0 & It is possible to check whether or not the touch panel is short-circuited by determining whether the value is greater than the third threshold value. That is, according to the present invention, whether or not the touch panel is short-circuited can be inspected with an easy method, and the defect of the touch panel can be inspected. Therefore, according to the present invention, it is possible to increase the number of sampling inspections or the total number of inspections of whether or not the touch panel is short-circuited, thereby reducing shipment of the bad touch panel.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

10, 110: touch panel 20, 200: touch panel drive circuit
21, 210: Tx driving circuits 22, 220: Rx driving circuit
30, 300: touch controller 100: stage
400: Good judgment part 500: Display device

Claims (17)

Supplying driving pulses to the Tx lines of the touch panel and converting the outputs of the sensor nodes received through the Rx lines to digital data to obtain touch row data;
Calculating filter data by applying a first filter to the touch row data;
Calculating a representative value of the number of filter data having a value larger than a first threshold value for each Tx line; And
And determining that the touch panel is a defective product when the case where the representative value has a value larger than the second threshold value is calculated. The method according to claim 1,
Wherein the first filter comprises:
And a differential filter applied in the Rx line direction. 3. The method of claim 2,
Wherein the first filter comprises:
Further comprising an average filter applied in the Tx line direction. The method according to claim 1,
Wherein the step of calculating, as a representative value, the number of filter data having a value larger than the first threshold value for each Tx line,
assigning "1" to the comparison value in the (j, k) coordinate when the filter data in the (j, k) coordinate has a value larger than the first threshold value;
Assigning "0" to the comparison value in the (j, k) coordinate when the filter data at the (j, k) coordinate has a large value less than or equal to the first threshold value; And
Assigning a sum of comparison values of a kth Tx line as a representative value of a kth Tx line,
j is a natural number satisfying 1? k? m, k is a natural number satisfying 1? k? n, m is the number of Rx lines and n is the number of Tx lines. Defective inspection method. Supplying driving pulses to the Tx lines of the touch panel and converting the outputs of the sensor nodes received through the Rx lines to digital data to obtain touch row data;
calculating sum of the touch row data for each Rx line by summing the touch row data of i (i is a natural number) frame period for each Rx line;
Calculating a number of cases in which the sum of the touch row data of one Rx line is equal to the sum of the touch row data of the neighboring Rx lines during the N frame period as a representative value of the one Rx line; And
And determining that the touch panel is a defective product when a case where the sum of representative values of any one of the Rx lines is equal to or greater than a third threshold value is calculated. 6. The method of claim 5,
Calculating the number of cases in which the sum of the touch row data of one Rx line is equal to the sum of the touch row data of the neighboring Rx lines during the N frame period as a representative value of the one Rx line,
Calculating differential value data for each Rx line by applying a second filter to the sum of touch row data calculated for each Rx line; And
And calculating a representative value of the number of differential data having a value of "0" for each of the Rx lines during the N frame period. The method according to claim 6,
And the second filter is a differential filter. A stage on which the touch panel is seated;
A touch panel driving circuit for supplying drive pulses to the Tx lines of the touch panel, converting the outputs of the sensor nodes received through the Rx lines to digital data and outputting touch row data; And
And a good quality determination unit for analyzing the touch row data to check whether the touch panel is short-circuited. 9. The method of claim 8,
The good-
Calculating filter data by applying a first filter to the touch row data, calculating a number of filter data having a value larger than a first threshold value for each Tx line as a representative value, Wherein the controller determines that the touch panel is a defective product when a case having a larger value is calculated. 10. The method of claim 9,
Wherein the first filter comprises:
And a differential filter applied in the Rx line direction. 11. The method of claim 10,
Wherein the first filter comprises:
Further comprising an average filter applied in the Tx line direction. 10. The method of claim 9,
The good-
1 "is assigned to the comparison value in the coordinate (j, k) when the filter data in the (j, k) coordinate has a value larger than the first threshold value, Quot; 0 "is assigned to the comparison value in the (j, k) coordinate when the data has a large value less than or equal to the first threshold value, and the sum of the comparison values of the k & Wherein j is a natural number satisfying 1? K? M, k is a natural number satisfying 1? K? N, m is the number of Rx lines, and n is the number of Tx lines A touch panel defect inspection device. 9. The method of claim 8,
The good-
(i is a natural number) frame period for each of the Rx lines to calculate a total sum of the touch row data for each Rx line. Then, the total sum of the touch row data of one Rx line during the N frame period is calculated The number of cases in which the sum of the touch row data of the adjacent Rx lines is equal to the sum of the touch row data of the neighboring Rx lines is calculated as a representative value of any one of the Rx lines and if the sum of the representative values of any one of the Rx lines is equal to or greater than the third threshold value, And judges that the touch panel is a defective product. 14. The method of claim 13,
The good-
Calculating a differential value data for each Rx line by applying a second filter to the sum of the touch row data calculated for each Rx line and calculating the number of differential value data having a value of "0" And calculates a representative value of the touch panel. 15. The method of claim 14,
And the second filter is a differential filter. 9. The method of claim 8,
The good-
Outputting a goodness-of-good determination signal of a first logic level indicating the defective product when it is determined that the touch panel is a defective product, and outputting a good-quality determination signal of a second logic level And outputs the detected result. 17. The method of claim 16,
And a display device for receiving a good product signal from the good quality determination unit and displaying a short circuit result of the touch panel.

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