KR20040103125A - Method for Driving Touch Panel - Google Patents

Abstract

PURPOSE: A method for driving a touch panel by using a hand touch rejection algorithm is provided to correct input by a hand not using a pen to an actual pen input value and display the actual pen input value by equipping with the hand rejection algorithm. CONSTITUTION: After the pen touches a touch surface, a coordinate value of a position is inputted to a controller of the touch panel in predetermined time intervals(2S). A change width between a present and a previous state of the coordinate values is calculated(3S). Hand rejection is selectively performed by judging that the change width is over a predetermined value or the coordinate value is corrected(5S). The coordinate value and an actual coordinate value found by performing the hand rejection are stored/displayed(17S).

Description

Method for Driving Touch Panel {Method for Driving Touch Panel}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a touch panel, and more particularly, to a method of driving a touch panel capable of correcting and displaying an actual pen input value with a hand rejection algorithm even when input by a hand other than a pen is present.

Hereinafter, a conventional touch panel will be described with reference to the accompanying drawings.

In order to efficiently use various electronic devices, a touch panel for inputting a signal on a display surface of a display device without a remote controller or a separate input device is widely used. That is, the display surface of an electronic notebook, a flat panel display device such as a liquid crystal display device (LCD), a plasma display panel (PDP), an electroluminescence (EL), and an image display device such as a cathode ray tube (CRT). The touch panel is installed. Accordingly, when the user presses the surface with a pen or finger on the screen of the image display device, information corresponding to the position is input.

The touch panel may be classified into a resistive type, a capacitive type, and an electromagnetic inductive type (EM) according to a method of sensing a touch.

The basic structure of the touch panel of the resistive type touch panel of the above touch panel is laminated with an upper transparent substrate on which the upper electrode is formed and a lower transparent substrate on which the lower electrode is formed with a predetermined space. Therefore, when a certain point of contact, such as a pen or a finger, is brought into contact with the upper substrate on which the upper electrode is formed, the upper electrode formed on the upper substrate and the lower electrode formed on the lower substrate are energized with each other, and the resistance of the position After reading the voltage value changed by the value, the device finds the position coordinate according to the change of the potential difference.

In addition, the basic structure of the capacitive touch panel of the above touch panel is to install a film with a transparent electrode on the liquid crystal panel and to apply a voltage to each corner or corner of the film to generate a uniform electric field on the transparent electrode. When a finger or a conductive stylus is applied to the device, a voltage drop is generated to find a position coordinate.

Referring to the conventional touch panel device as described above with reference to the accompanying drawings as follows.

1 is an explanatory diagram showing a conventional resistive touch panel device.

In the conventional touch panel device, as shown in FIG. 1, the touch panel 10 outputting the coordinate signal of the touch point, and the coordinate signal from the touch panel 10 by controlling the driving of the touch panel 10. And a system 40 for performing a corresponding command in response to the coordinate values from the touch panel controller 30. .

The touch panel 10 is provided with an upper film 12 and a lower film 16, the first transparent conductive layer 14 is formed on the upper film 12 of the surface facing each other, the surface facing each other A second transparent conductive layer 18 is formed on the lower film 16, so that the upper film 12 and the lower film 16 are spaced at a predetermined interval.

The upper film 12 and the lower film 16 are bonded by the adhesive 22 at the outer portion of the non-touch area and spaced apart by the height of the adhesive 22. In addition, a plurality of dot spacers 20 may be formed on the first transparent conductive layer 14 or the lower film 16 of the upper film 12 to separate the upper film 12 from the lower film 16 in the touch area. It is further formed on the second transparent conductive layer 18.

As the upper film 12 pressed by a pen or a finger, a transparent film such as polyethylene terephthalate (PET) is mainly used, and the lower film 16 is a transparent film of the same material as the upper film 12 or a glass substrate. Or a plastic substrate is used. The first and second transparent conductive layers 14 and 18 formed on the upper and lower films 12 and 16 may include indium tin oxide (ITO), indium zinc oxide (IZO), and indium tin zinc oxide (ITZO). Either one is used.

The touch panel 10 includes an X-electrode bar 15 connected to both sides of the first transparent conductive layer 14 to apply a voltage to the first transparent conductive layer 14 in the X-axis direction. The second transparent conductive layer 18 further includes a Y-electrode bar 19 connected to both sides of the second conductive layer 18 to apply a voltage in the Y-axis direction. The X-electrode bar 15 includes a first X-electrode bar 15a and a ground voltage GND for supplying a driving voltage Vcc so that current flows in the X-axis direction to the first transparent conductive layer 14. It consists of a second X-electrode bar (15b) for supplying. The Y-electrode bar 19 has a second Y-electrode bar 19b and a ground voltage GND for supplying a driving voltage Vcc so that current flows in the Y-axis direction to the second transparent conductive layer 16. It consists of a first Y-electrode bar (19a) for supplying.

In the touch panel 10, when the pen or finger presses the upper film 12 to make the first transparent conductive layer 14 contact the second transparent conductive layer 18, the first and second touch panels 10 may be touched according to their contact positions. The resistance value varies depending on the sheet resistance that the transparent conductive layers 14 and 18 contact. Since the current or voltage is changed according to the variable resistance value, the first or second Y-electrode bar 19a connected to the second transparent conductive layer 18 may be used to change the current or voltage. or 19b) to output the X-axis coordinate signal, and output the Y-axis coordinate signal through the first or second X-electrode bars 15a or 15b connected to the first transparent conductive layer 14. In this case, the touch panel 10 sequentially outputs the X-axis coordinate signal and the Y-axis coordinate signal under the control of the touch panel controller 30.

In detail, when the driving voltage Vcc and the ground voltage GND are supplied to the X-electrode bar 15 through the first switch 24, the touch panel 10 may have the first and second transparent conductive layers 14. , 18 outputs an X-axis coordinate signal through the first Y-electrode bar 19a and the second switch 26 in response to the resistance value changed by the contact point. Subsequently, when the driving voltage Vcc and the ground voltage GND are supplied to the Y-electrode bar 19 through the first and second switches 24 and 26, the touch panel 10 is first and second transparent. The Y-axis coordinate signal is output through the second X-electrode bar 15b in response to a resistance variable by the point where the conductive layers 14 and 18 contact.

Here, the first switch 24 may drive the driving voltage Vcc in response to the control signal CS from the touch panel controller 30 to the first X-electrode bar 15a or the second Y-electrode bar 19b. ) Will be supplied. The second switch 26 transfers the ground voltage GND to the second X-electrode bar 15b or the first Y-electrode bar 19a in response to the control signal CS from the touch panel controller 30. Outputs the voltage of the supplied or touched position.

The touch panel controller 30 detects the coordinate values according to the X-axis and Y-axis coordinate signals of the touch point output from the touch panel 10 and supplies them to the system 40. In addition, the touch panel controller 30 controls the first and second switches 24 and 26 according to the X-axis coordinate mode and the Y-axis coordinate mode to control power supply (Vcc, GND) to the touch panel 10. Done.

To this end, the touch panel controller 30 includes an analog-to-digital converter (hereinafter referred to as an ADC) 32 and an ADC 32 for converting X-axis and Y-axis coordinate signals from the touch panel 10 into digital data. The microcomputer 34 which detects the coordinate values by the combination of the X-axis and the Y-axis coordinate data from 36).

The ADC 32 converts each of the X-axis coordinate signal and the Y-axis coordinate signal sequentially supplied from the touch panel 10 into digital data and outputs the digital data.

The microcomputer 34 combines the X-axis and Y-axis coordinate data sequentially supplied from the ADC 32 to detect the coordinate value of the touch point of the touch panel 10, and converts the detected coordinate value into the interface unit 36. To the system 40 through. In addition, the microcomputer 34 generates the control signal CS at regular intervals so that the first switch 24 sets the driving voltage Vcc to the first X-electrode bar 15a or the second Y-electrode bar 19b. The second switch 26 supplies the ground voltage GND to the first X-electrode bar 15b or the first Y-electrode bar 19a and outputs a voltage according to the touch.

The system 40 detects a coordinate value supplied from the touch panel controller 30 and executes a corresponding command or executes an application program related thereto by the coordinate value. The system 40 also supplies power signals and video data for a display (not shown) on which the touch panel 10 is mounted on a surface.

As described above, the conventional touch panel device detects a coordinate value pressed by a pen or a finger and transmits the coordinate value to the system 40 to perform a command corresponding to the coordinate value in the system 40.

However, in the touch panel 10 as described above, due to user's carelessness, a double touch may occur by simultaneously touching the upper film 12 with a pen and a finger.

2 is a cross-sectional view illustrating a dual touch phenomenon in which a pen and a hand are simultaneously touched in the touch panel.

As illustrated in FIG. 2, when a character is input or drawn using a pen, the side of the hand holding the pen may also press the touch surface (upper substrate 12) of the touch panel. In this case, the touch panel generates a double touch, that is, a pen touch point T1 and a hand touch point T2. The pen touch point T1 and the hand touch point T2 may occur simultaneously, or alternatively, only one of the two may occur.

In this case, when the pen touch point T1 and the hand touch point T2 are generated at the same time, the touch panel generates coordinate signals for intermediate points between the two points T1 and T2. The 40 recognizes an intermediate point as a pen touch point and commits an error reflected on the display.

In addition, when the hand touch point T2 occurs while the pen touch point is generated after the pen touch point T1, the touch panel generates a first coordinate signal for the pen touch point T1, and then the pen touch point. A second coordinate signal is generated for an intermediate point between T1 and the hand touch point T2. When the first and second coordinate signals are generated within a unit time for detecting the coordinate values in the touch panel controller 30, the touch panel controller 30 detects the coordinate values of the second coordinate signals input later and generates a system ( Since 40 is supplied to the system 40, the system 40 makes an error of recognizing the intermediate point as the pen touch point T1.

However, the above conventional driving method of the touch panel has the following problems.

In the conventional resistive touch screen, when the pen and the hand are in contact with the panel surface at the same time, a phenomenon occurs in which the display is made in the middle portion of the contact portion between the pen and the hand.

Therefore, this point of recognizing the hand touch to the same level as the pen in the resistive method has been pointed out as the biggest problem compared to other methods.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and even though there is an input by a hand other than a pen, a touch panel driving method capable of correcting and displaying a real pen input value with a hand rejection algorithm is provided. To provide it, its purpose is.

1 is an exploded perspective view showing a conventional resistive touch panel and a block diagram showing a power supply related control unit of the touch panel;

Figure 2 is a schematic cross-sectional view showing a double touch of the pen and the hand holding the pen on the touch surface of the touch panel

3 is an exploded perspective view showing a touch panel used in the method for driving a touch panel of the present invention, and a block diagram showing a power supply related control unit of the touch panel;

4A is a diagram illustrating a method of detecting a contact resistance of a dual touch, and FIG. 4B is an equivalent circuit diagram thereof.

5A to 5C are graphs according to states when the hand touch mode is switched from the normal mode, the hand touch mode, and the normal mode is switched from the hand touch mode, respectively.

6 is a view showing a warning window generated when switching the hand touch mode of the present invention.

7 is a block diagram of a touch panel of the present invention.

8 is a flowchart illustrating a method of driving a touch panel of the present invention.

* Description of symbols on the main parts of the drawings *

50: touch panel 52: upper film

54: first transparent conductive film 56: lower substrate

58: second transparent conductive film 60: dot spacer

64, 66: switch 70: touch panel controller

72: analog-to-digital converter (ADC) 74: microcomputer

76: interface unit 80: system

55: X-electrode bar 55A: First X-electrode bar

55B: second X-electrode bar 59: Y-electrode bar

59A: first Y-electrode bar 59B: second Y-electrode bar

110: coordinate receiving unit 112: coordinate calculating unit

114: hand reject processing unit 116: coordinate display unit

118: central processing unit 122: memory

124: compensation

According to an aspect of the present invention, there is provided a method of driving a touch panel, the method comprising: inputting coordinate values (x _en, y _en ) of a predetermined position to a controller of a touch panel at predetermined time intervals after pen contact of a touch surface; Calculating a change width Δx _n , Δy _n of the current state and the previous state of the coordinate value, and determining whether the change in the coordinate value Δx _n , Δy _n is greater than or equal to a predetermined value and compensates for the coordinate value Selectively performing hand rejection, and storing the coordinate values (x _en, y _en ) and the actual coordinate values (x _rn, y _rn ) obtained in the hand rejection, and then displaying the coordinates. Has its features.

When the coordinate value change width Δx _n , Δy _n is greater than a predetermined value and there is no previous coordinate value compensation, a dual touch message and a continuous selection message are output.

In response to the progress selection message, the first hand rejection is performed after determining as a dual touch.

The primary hand rejection is performed by subtracting a coordinate change width Δx _n and Δy _{n from} the coordinate values x _{en and} y _en at the predetermined position.

When the coordinate value change width Δx _n , Δy _n is equal to or greater than a predetermined value and there is a previous coordinate value compensation, the input coordinate value is output as a real coordinate value after determining that the dual touch is released.

When the coordinate value change width Δx _n , Δy _n is less than a predetermined value and there is a previous coordinate value compensation, the second hand rejection is performed after determining that the dual touch is maintained.

The second hand rejection is performed by adding twice the value of the coordinate change width Δx _n and Δy _{n to} the actual coordinate values x _{r (n-1)} and y _{r (n-1)} of the previous position. Coordinate correction is made.

When the coordinate value change width Δx _n , Δy _n is less than a predetermined value and there is no previous coordinate value compensation, the input coordinate value is output as a real coordinate value after determining that it is a normal touch.

In addition, the touch panel driving method of the present invention for achieving the same object is a first step of sequentially inputting the _touched coordinate values (x _en, y _en ) at a predetermined time interval, and the change width (Δx) of the input coordinates a second step of measuring _n , Δy _n ) to determine whether the change width is greater than or equal to the set value, and a third step of determining whether the coordinate value is compensated before the change width is greater than or equal to the set value in the second step, and the third step In the fourth step of first hand rejecting the input coordinate value by judging by double touch if there is no coordinate value compensation before and in the third step, by determining the double touch release in the third step, the input coordinate value is determined. Another feature is that the method includes a fifth step of recognizing a real coordinate value (x _rn, y _rn ).

The primary hand rejection is performed by subtracting the coordinate change width Δx _n and Δy _n from the input coordinate values x _{en and} y _en .

In the second step, if the change width is less than or equal to the set value, it is determined whether the coordinate value has been compensated before, and if there is the coordinate value compensation, the second hand rejection of the input coordinate value (x _en, y _en ) is performed to correct the actual coordinate. A step is made.

The second hand rejection is performed by adding twice the value of the coordinate change width Δx _n and Δy _{n to} the actual coordinate values x _{r (n-1)} and y _{r (n-1)} of the previous position. Coordinate correction is made.

In the second step, if the change width is less than or equal to the set value, it is determined whether the coordinate value has been compensated before. If there is no coordinate value compensation, the method further includes a seventh step of recognizing the input coordinate value (x _en, y _en ) as the actual coordinate value. do.

The method may further include an eighth step of determining that the abnormal touch is released if the coordinate value compensation has been performed in the third step.

And storing the coordinate change width in the fourth step.

Hereinafter, a driving method of the touch panel of the present invention will be described in detail with reference to the accompanying drawings.

3 is an exploded perspective view showing a touch panel used in the method for driving a touch panel of the present invention and a block diagram showing a power supply related control unit.

As shown in FIG. 3, the touch panel of the present invention controls the driving of the touch panel 50, which outputs the coordinate signal of the touch point, and controls the driving of the touch panel 50 and adjusts the coordinate values according to the coordinate signal from the touch panel 50. The touch panel controller 70 detects and outputs the system 80, and a system 80 for executing a corresponding command in response to the coordinate values from the touch panel controller 70.

The touch panel 50 includes an upper film 52 on which first transparent conductive layers 54 are formed, and a lower film 56 on which second transparent conductive layers 58 are formed, respectively. The upper film 52 and the lower film 56 are bonded at a predetermined interval apart.

The upper film 52 and the lower film 56 are bonded by an adhesive 62 at an outer portion of the non-touch area and spaced apart by the height of the adhesive 62. In addition, a plurality of dot spacers 60 may be formed on the first transparent conductive layer 54 or the lower film 56 of the upper film 52 to separate the upper film 52 and the lower film 56 from the touch area. It is further formed on the second transparent conductive layer 58.

As the upper film 52 pressed by a pen or a finger, a transparent film such as polyethylene terephthalate (PET) is mainly used, and the lower film 56 is a transparent film of the same material as the upper film 52 or a glass substrate. Or a plastic substrate is used. Indium-tin-oxide (ITO), indium-zinc-oxide (IZO), or indium-tin-zinc-oxide (ITZO) may be used as the first and second transparent conductive layers 54 and 58. do.

The touch panel 50 may include an X-electrode bar 55 connected to both sides of the first transparent conductive layer 54 to apply a voltage to the first transparent conductive layer 54 in the X-axis direction. The second transparent conductive layer 58 further includes a Y-electrode bar 59 connected to both sides of the second transparent conductive layer 58 to apply a voltage in the Y-axis direction. The X-electrode bar 55 includes a first X-electrode bar 55a and a ground voltage GND for supplying a driving voltage Vcc so that current flows in the X-axis direction to the first transparent conductive layer 54. It consists of a second X-electrode bar (55b) for supplying. The Y-electrode bar 59 includes a first Y-electrode bar 59a and a ground voltage GND for supplying a driving voltage Vcc so that current flows in the Y-axis direction to the second transparent conductive layer 56. It consists of a second Y-electrode bar (59b) for supplying.

The touch panel 50 has a sheet resistance of the transparent conductive layer according to the contact position when a pen or a finger presses the upper film 52 to make the first transparent conductive layer 54 contact the second transparent conductive layer 58. Because of this difference, the resistance value is variable. In addition, since the current or voltage is changed according to the variable resistance value, the second Y-electrode bar 59b is applied to the changing current or voltage when the voltage is applied to the first transparent conductive layer 54. The X-axis coordinate signal is output through the X-axis coordinate signal, and the Y-axis coordinate signal is output through the second X-electrode bar 55b when a voltage is applied to the second transparent conductive layer 58. In this case, the touch panel 50 sequentially outputs the X-axis coordinate signal and the Y-axis coordinate signal under the control of the touch panel controller 70.

In detail, when the driving voltage Vcc and the ground voltage GND are supplied to the X-electrode bar 55 through the first and second switches 64 and 66, the first and second touch panels 50 may be used. The X-axis coordinate signal is output through the second Y-electrode bar 59b in response to a resistance variable by the point where the transparent conductive layers 54 and 58 are in contact. Subsequently, when the driving voltage Vcc and the ground voltage GND are supplied to the Y-electrode bar 59 through the first and second switches 64 and 66, the touch panel 50 is provided with the first and second transparent conductive materials. The Y-axis coordinate signal is output through the second X-electrode bar 55b in response to the resistance variable by the point where the layers 54 and 58 contact.

Here, the first switch 64 may drive the driving voltage Vcc in response to the control signal CS from the touch panel controller 70. The first X-electrode bar 55a or the first Y-electrode bar 59a may be used. To be supplied. The second switch 66 supplies the base voltage GND to the second X-electrode bar 55b or the second Y-electrode bar 59b in response to the control signal CS from the touch panel controller 70. Or output voltage.

The touch panel controller 70 detects the coordinate values according to the X-axis and Y-axis coordinate signals of the touch points supplied from the touch panel 50 and supplies them to the system 80. The touch panel controller 70 controls the first and second switches 64 and 66 to control the supply of power (Vcc, GND) to the touch panel 50.

To this end, the touch panel controller 70 includes an analog-to-digital converter (hereinafter referred to as an ADC) 72 and an ADC 72 for converting X-axis and Y-axis coordinate signals from the touch panel 50 to digital data. The microcomputer 74 detects and outputs coordinate values to the system 80 by the combination of the X-axis and Y-axis coordinate data from the control unit, and an interface unit for relaying the coordinate values from the microcomputer 74 to the system 80. 76 is provided.

The ADC 72 converts each of the X-axis coordinate signal and the Y-axis coordinate signal sequentially supplied from the touch panel 50 into digital data and outputs the digital data.

The microcomputer 74 generates the control signal CS in a predetermined time unit so that the first switch 64 transmits the driving voltage Vcc to the first X-electrode bar 55a or the first Y-electrode bar 59a. The second switch 66 causes the base voltage GND to be supplied to the second X-electrode bar 55b or the second Y-electrode bar 59b. Accordingly, the microcomputer 74 detects the coordinate value of the touch point of the touch panel 50 by combining the X-axis and Y-axis coordinate data sequentially supplied from the ADC 72, and converts the detected coordinate value into the interface unit 76. To the system 80).

At this time, it is determined whether the pen and the hand are touched at the same time or both within the predetermined time in the microcomputer 74 or the system 80 to prevent errors due to the double touch in software and coordinates at that time. Compensate for the value.

4A is a diagram illustrating a method of detecting a contact resistance of a dual touch, and FIG. 4B is an equivalent circuit diagram thereof.

As shown in FIG. 4A, the first X- of the first transparent conductive layer 54 on the upper film 52 side to detect the contact resistance between the pen touch point T1 and the hand touch point T2 when a dual touch occurs. The first Y-electrode bar 59a of the second transparent conductive layer 58 on the lower film 56 side with the power supply voltage applied to the electrode bar 55a and the second X-electrode bar 55b open. ) Is grounded, and the second Y-electrode bar 59b is connected to the touch panel controller 70 to calculate the corresponding voltage of the touch region, and then calculate a predetermined position according to the corresponding voltage.

At this time, as shown in FIG. 4B, since the contact areas between the pen touch point T1 and the first and second conductive layers 54 and 58 of the hand touch point T2 are different, the contact between the pen touch points T1 is different. Since the resistance is Rcp and the hand touch point T2 is larger in area than the pen touch point T1, the contact resistance of the hand touch point T2 can be calculated as Rcp-α. The contact resistance between the pen touch point T1 and the hand touch point T2 is the first transparent conductive layer 54 with the power supply voltage Vcc and the second transparent conductive layer 58 with the ground voltage Vss. It is similar to functioning as parallel resistance (Rall = Rcp // (Rcp-α)) connected in parallel between them, and in the following, contact resistance and actual calculated voltage according to the presence or absence of pen touch and hand touch at a predetermined position point Verify this through the data in the value and current.

Table 1 is a table showing voltage, resistance, and current values according to the previous state and the current state of each situation when the touch operation is performed at a predetermined position on the touch surface.

Contact resistance Voltage (V) Resistance (Ω) Current (mA) condition Previous state Current Status One X Rcp X 3.8 X 634 6 Pen only contact 2 X Rcp-α X 3.15 X 394 8 Hand only contact 3 Rcp Rall 3.8 2.42 634 242 10 Hand contact after pen contact 4 Rall Rcp 2.42 3.8 242 634 6 Only release hand after double contact 5 Rall Rcp-α 2.3 2.6 242 325 8 Only release the pen after double contact 6 Rcp X 3.8 X 634 X 0 Pen contact release 7 Rcp-α X 3.15 X 8 X 0 Hand contact

As shown in Table 1, when the touch by the pen occurs at the site showing a voltage value of 3.8V, the voltage values when the pen and the hand double-contact at the same time are 3.15V, 2, and 42V, respectively.

That is, when a contact other than the pen is made, the voltage value corresponding to the coordinate value falls, and it can be seen that this indicates a voltage value that is farther when a double contact between the pen and the hand occurs than the contact of the hand only. This is because a dual contact resistance (Rall = Rcp // Rcp-α), which is smaller than the hand contact resistance (Rcp-α), is formed because the above-described contact resistance is connected in parallel in parallel resistance.

Therefore, if there are any hand touches other than the pen, the voltage value of the touch point is measured at the predetermined time intervals to determine a portion having a change (ΔVx, ΔVy) of a predetermined value (K) or more in the previous state and the present state. After judging by the point of double touch and outputting a warning message to determine whether to proceed, the position is detected by correcting the coordinate value through the hand rejection program of the touch panel controller 70 and proceeding. When the process is stopped, it is determined that only the hand touches and the position determination of the touch panel is stopped until the touch by the next pen. Hereinafter, a change in the predetermined value of the previous state and the current state is calculated by using a coordinate value corresponding to the voltage value instead of the voltage value, and the coordinate value change width is compared with a predetermined coordinate change value to determine whether there is an abnormal touch. .

5 is a view showing a warning window generated when switching the hand touch mode of the present invention.

When there is a voltage value change over a predetermined value in a previous state and a current state, as shown in FIG. 6, a warning message indicating that there is a contact other than a pen is output, and a selection is made to continue. For example, when only the touch of the hand is made, the continuous process is stopped, and in the case of the dual touch of the pen and the hand, the continuous process is selected to perform the hand rejection so that a normal pen coordinate value is output.

On the other hand, when only a hand touch except a pen is made, a warning message is output and the input of a coordinate value is ignored. Hereinafter, a hand touch rejection proceeding when a hand touch is added in the pen touch will be described.

6A to 6C are graphs according to states when the dual touch mode is switched from the normal mode, the dual touch mode is maintained, and the normal mode is switched from the dual touch mode, respectively.

As shown in FIG. 6A, when switching from the normal mode (touch only of the pen) to the dual touch mode (pen and hand touch), the touch panel controller primarily switches the second coordinate value (pen touch) from the first coordinate value (x _e1 , y _e1 ). It is recognized as a variation between (x _e2 , y _e2 ) and the hand touch. That is, at this time, the coordinate value change Δ1 = (Δx ₁ , Δy ₁ ) = ((x _e2 -x _e1 ), (y _e2 -y _e1 )).

In the normal mode, since the first coordinate values x _e1 and y _e1 are actual coordinate values, the first coordinate values are output as the first real coordinate values x _r1 and y _r1 without performing hand rejection.

When switching to the dual touch mode, the primary second coordinate value may vary for each unit time of recognizing the coordinate value for the touch area, but if the unit time is minimized as much as possible, the change in the actual coordinate value of the pen may be almost insignificant. Thus, the first real coordinate value and the second real coordinate value will be almost similar.

Therefore, when the first coordinate change value Δ1 = (Δx ₁ , Δy ₁ ) becomes greater than or equal to a set value, it is determined that the dual touch mode has been entered, and in this case, the second real coordinate values (x _r2 , y _r2 ) are It can be said that the second coordinate value (x _e2 , y _e2 ) after the hand touch is similar to the value (x _e2 -Δx ₁ , y _e2 -Δy ₁ ) obtained by subtracting the first coordinate change value.

As shown in FIG. 6B, in the dual touch mode, the second coordinate change value Δ2 = (Δx ₂ , Δy ₂ ) is obtained by subtracting the second coordinate value from the third coordinate value (x _e3 -x _e2 , y _e3 -y). _e2 ), where the third real coordinate value (x _r3 , y _r3 ) of the actual pen is equal to the value obtained by doubling the second coordinate change value to the second real coordinate value. Therefore, the third real coordinate value becomes (x _r3 , y _r3 ) = ((x _r2 + 2x ₂ ), (y _r2 + 2y ₂ )).

As shown in FIG. 6C, when switching from the dual touch mode to the normal mode, as shown in FIG. 5A, when the third coordinate value change value Δ3 = (Δx ₃ , Δy ₃ ) is larger than a predetermined value, the fourth mode of the normal mode is used. The real coordinate values x _r4 and y _r4 output the fourth coordinate values x _e4 and y _e4 as they are.

7 is a block diagram related to hand rejection of a touch panel of the present invention.

As shown in FIG. 7, the system 80 compensates an error coordinate value due to a dual touch transmitted from the touch panel controller 70 by using a central processing unit (CPU) 118 having a high processing speed and a pen touch point. It will detect the true true coordinate value for. In addition, the system 80 supplies power signals and video data necessary for a display (not shown) in which the touch panel 50 is mounted on a surface.

To this end, the system 80 includes a central processing unit 118 and a touch panel driver 82 for compensating for error coordinate values due to dual touch.

The touch panel driver 82 displays a coordinate receiving unit 110 for receiving a digital coordinate value transmitted from the touch panel controller 70 and a communication protocol for the digital coordinate value received from the coordinate receiving unit 110. The coordinate calculation unit 112 resets the received digital coordinate value to correspond to the resolution, and calculates the change width of the reset coordinate value in the coordinate calculation unit 112, and if the calculated coordinate change value is equal to or greater than a predetermined value, determines by double touch. Coordinates for displaying the true coordinate values compensated by the hand reject processing unit 114 and the hand reject processing unit 114 to generate the true coordinate values by compensating the digital coordinate values reset by the coordinate calculating unit 112 on the display. The display unit 116 is provided.

The coordinate calculator 112 resets the digital coordinate value received by the coordinate receiver 110 to match the communication protocol of the display resolution (XGA, SVGA, etc.) and supplies the digital coordinate value to the hand rejection processor 114. do.

The hand rejection processor 114 calculates a change width of the coordinate value received from the coordinate calculation unit 112, and the calculated coordinate change width is equal to or greater than a predetermined value, and the input coordinate value is determined as a double touch when the coordinate operation continues. Is corrected to be displayed on the actual display. At this time, the hand rejection processor 114 corrects the error coordinate value generated by the dual touch using the central processing unit 118 having a high processing speed.

To this end, the hand rejection processor 114 may store the reset coordinate values supplied from the coordinate calculation unit 112 and the new coordinates supplied from the coordinate calculation unit 112 and the coordinate values stored in the memory 122. The compensation unit 124 calculates the coordinate change width using the value and determines the error coordinate value due to the double touch when the calculated change width is greater than or equal to a predetermined value.

The memory 122 stores sequential coordinate values of the touch panel 50 detected by the touch controller 70.

8 is a flowchart illustrating a method of driving a touch panel of the present invention.

As shown in FIG. 8, the touch panel is driven by setting the initial touch operation of the touch surface to the initializing (N = 0) state 1S.

The microcomputer 74 of the touch panel controller 70 controls the first and second switching units 64 and 66 at intervals of a predetermined time (for example, 3.4 ms) and is converted into digital values through the ADC 72. The x and y position coordinate values (x _en and y _en ) are output (2S).

Accordingly, the system 80 inputs coordinate values (x _en , y _en ) output from the touch panel controller 70 in a state of initializing (N = 0) (1S). The input coordinate values are compared to calculate coordinate change values Δx _n and Δy _n of the previous state and the current state (3S).

That is, the hand rejection processor 114 compares the coordinate values reset by the coordinate calculator 112 to suit the communication protocol of the display resolution (XGA, SVGA, etc.) and calculates two successive coordinate change widths. At this time, the coordinate change width calculates the change widths Δx _n , Δy _n in the X-axis direction and the Y-axis direction, respectively.

Then, it is determined whether the calculated coordinate change widths Δx _n and Δy _n in the X-axis or Y-axis direction are equal to or greater than a predetermined value K (4S). 1?), And when there is no coordinate value compensation, the input coordinate value (x _en , y _en ) is determined as the actual coordinate value (x _rn , y _rn ) (6S), and then the input coordinate value (x _en , y _en ) (17S).

Subsequently, the power off is determined (18S), and the input coordinate values x _en and y _en are continuously displayed until the power off occurs.

If at least one of the coordinate change widths Δx _n and Δy _n is equal to or greater than a predetermined value K, it is determined (7S) whether there has been a coordinate value compensation (N = 1?) Before, and when there is no compensation, an abnormal touch is performed. Judgment is made to ask whether or not to proceed (8S).

At this time, when it is determined that there is only a touch of the hand (hand) or when it is necessary to initialize again from the beginning and proceed again, the user stops the process and proceeds to the initialization state again.

Otherwise, if it selects to proceed, it is determined as a dual touch (9S) and the true coordinate correction is performed for the dual touch.

That is, when there is no coordinate value compensation, when it is determined 9S as a dual touch, the coordinate change values Δx _n and Δy _n are applied to the coordinate values x _en and y _en inputted to the controller 70 of the touch panel. The primary coordinate value compensation is performed by subtracting the value (10S). Therefore, the hand rejected real coordinate values (x _rn , y _rn ) are (x _en -Δx _n , y _en -Δy _n ).

Subsequently, the primary compensated real coordinate values (x _rn and y _rn ) are stored (11S) and a value corresponding to the real coordinate values (x _rn and y _rn ) is displayed (17S).

When the coordinate change widths Δx _n and Δy _n are less than a predetermined value K, it is determined that the double touch is maintained when it is determined that there is coordinate value compensation (N ≠ 1) (12S), and second hand rejection. (13S). At this time, the actual coordinate value (x _rn , y _rn ) of the secondary coordinate value compensation is twice the width of the coordinate change in the actual coordinate values (x _{r (n-1)} , y _{r (n-1)} ). (Δx _n , Δy _n ) is added. That is, the second-compensated real coordinate values x _rn and y _rn become (x _{r (n-1)} + 2Δx _n , y _{r (n-1)} + 2Δy _n ). In operation 14S, the real coordinate value is stored.

When the coordinate change widths Δx _n and Δy _n are equal to or greater than a predetermined value, when it is determined that there is coordinate value compensation (N = 1), it is determined that the abnormal touch is released (15S), and then the input coordinate values (x _en , y _en ) are stored as actual coordinate values (x _rn , y _rn ) (16S).

As described above, after the input coordinate value or the actual coordinate correction is selectively performed according to the coordinate change width and the coordinate value compensation, each coordinate value is stored and displayed (17S).

The display of these input coordinate values or corrected true coordinate values is continued until it is determined to be power off.

That is, as described above, since the microcomputer switches the first and second switching units 64 and 66 at intervals of about 3.4 ms, the coordinate values are output from the touch panel controller 70 at least every 3.4 ms. At this time, when the coordinates are normally output instead of the double touch, the set values K do not deviate in the X-axis or Y-axis directions at the 3.4 ms intervals. Here, the setting value K is a unit of the census value reset to suit the communication protocol of the resolution (XGA, SVGA, etc.) of the display device, and thus is not a distance, but a value according to the resolution.

Of course, when drawing a line at a very high speed, it may be out of the range, but since the actual coordinate change is not so large due to the characteristic of the touch panel in which the coordinate value is detected at a predetermined time unit, the abnormal touch is determined by the change of the predetermined value. The principle is fully applicable.

According to the driving method of the touch panel of the present invention, since all touches other than the pen are determined as abnormal touches, an error message is output and notified to the user, and thus all abnormal touches generated after the touch operation on the touch panel can be controlled.

After the double touch between the pen and the hand occurs, the first compensation is performed by subtracting the detected coordinate value to the coordinate change value, and then, if the double touch occurs continuously, the coordinate change width is applied to the first compensated real coordinate value of the whole state. By performing the second compensation that adds the value of 2 times, it is possible to deviate from the conventional correction method only for the moment when the double touch occurs, and hand rejection is possible even if the double touch occurs continuously.

The driving method of the touch panel of the present invention as described above has the following effects.

First, since all touches other than the pen are determined to be abnormal touches, an error message is output and notified to the user.

In other words, if only the touch of the hand occurs or if the double touch between the pen and the hand is judged as an abnormal touch, a warning message is output in each case and the user can select whether to proceed or not so that the hand only wants the user's judgment. You can proceed with the rejection.

Second, after the double touch between the pen and the hand occurs, the first compensation is performed by subtracting the detected coordinate value to the coordinate change value, and then, if the double touch occurs continuously, the coordinate change width is applied to the first compensated real coordinate value of the whole state. By performing the second compensation that adds the value of 2 times, it is possible to deviate from the conventional correction method only for the moment when the double touch occurs, and hand rejection is possible even if the double touch occurs continuously.

Claims (15)

Inputting a coordinate value (x _en, y _en ) of a predetermined position to a controller of the touch panel at predetermined time intervals after pen contact of the touch surface; Calculating a change width (Δx _n , Δy _n ) between the current state and the previous state of the coordinate value; Selectively performing hand rejection by determining whether the coordinate value change width Δx _n , Δy _n is greater than or equal to a predetermined value and whether the coordinate value is compensated; And And storing the coordinate values (x _en, y _en ) and the actual coordinate values (x _rn, y _rn ) obtained by performing the hand rejection, and then displaying the coordinate values (x _en, y _en ). The method of claim 1, And outputting a dual touch message and a continuous selection message when the coordinate value change widths Δx _n and Δy _n are greater than or equal to a predetermined value and there is no previous coordinate value compensation. The method of claim 2, And a first hand rejection after determining as dual touch when continuing response to the continued selection message. The method of claim 3, wherein And the primary hand rejection is a real coordinate correction by subtracting a coordinate change width (Δx _n , Δy _n ) from the coordinate values (x _en, y _en ) of the predetermined position. The method of claim 1, When the coordinate value change width Δx _n , Δy _n is greater than or equal to a predetermined value and there is a previous coordinate value compensation, it is determined that the dual touch is released, and then the input coordinate value is output as a real coordinate value. Way. The method of claim 1, And when the coordinate value change width Δx _n and Δy _n are less than a predetermined value and there is a previous coordinate value compensation, the second hand rejection is performed after determining that the dual touch is maintained. The method of claim 6, The second hand rejection is performed by adding twice the value of the coordinate change width Δx _n and Δy _{n to} the actual coordinate values x _{r (n-1)} and y _{r (n-1)} of the previous position. Method of driving a touch panel, characterized in that the coordinate correction is made. The method of claim 1, When the coordinate value change width Δx _n , Δy _n is less than a predetermined value and there is no previous coordinate value compensation, the touch panel driving method outputs an input coordinate value as a real coordinate value after determining that it is a normal touch. . A first step of sequentially inputting coordinate values x _{en and} y _{en touched} at regular time intervals; A second step of determining whether the change width is greater than or equal to a set value by measuring a change width Δx _n and Δy _n of the input coordinates; A third step of determining whether a coordinate value is compensated before the change width is greater than or equal to a preset value in the second step; A fourth step of first hand rejecting the inputted coordinate value by determining as a dual touch if there is no coordinate value compensation before the third step; And a fifth step of recognizing the input coordinate value as a real coordinate value (x _rn, y _rn ) if the coordinate value compensation was previously performed in the third step. Way. The method of claim 9, The primary hand rejection method is a touch panel driving method, characterized in that the actual coordinate correction is made by subtracting the coordinate change width (Δx _n , Δy _n ) to the input coordinate values (x _en, y _en ). The method of claim 9, In the second step, if the change width is less than or equal to the set value, it is determined whether the coordinate value has been compensated before, and if there is the coordinate value compensation, the second hand rejection of the input coordinate value (x _en, y _en ) is performed to correct the actual coordinate. Method of driving a touch panel, characterized in that comprises a step. The method of claim 11, The second hand rejection is performed by adding twice the value of the coordinate change width Δx _n and Δy _{n to} the actual coordinate values x _{r (n-1)} and y _{r (n-1)} of the previous position. Method of driving a touch panel, characterized in that the coordinate correction is made. The method of claim 9, In the second step, if the change width is less than or equal to the set value, it is determined whether the coordinate value has been compensated before. If there is no coordinate value compensation, the method further includes a seventh step of recognizing the input coordinate value (x _en, y _en ) as the actual coordinate value. Method of driving a touch panel, characterized in that. The method of claim 9, And an eighth step of determining that the abnormal touch is released if there is a coordinate value compensation before the third step. The method of claim 9, And storing the coordinate change width in the fourth step.