WO2013122287A1

WO2013122287A1 - Driving electrode pattern, touch panel, touch panel module, and electronic device including the same

Info

Publication number: WO2013122287A1
Application number: PCT/KR2012/002604
Authority: WO
Inventors: Sung Han Kim; Kyoung Kyoo KIM; Hyung Cheol Shin; Il Hyun Yun
Original assignee: Zinitix Co., Ltd.
Priority date: 2012-02-15
Filing date: 2012-04-05
Publication date: 2013-08-22
Also published as: KR20130094131A; KR101372329B1

Abstract

Provided are a driving electrode pattern, a touch panel, a touch panel module, and an electronic device. The touch panel includes at least one driving electrode extending in a first direction, and a sensing electrode extending in a different direction than the first direction. One of the at least one driving electrode includes a plurality of sub electrodes extending in the first direction and disposed in parallel, end parts at one side of the plurality of sub electrodes are directly connected to each other, and the plurality of sub electrodes are spaced from each other by a predetermined size of a gap at other parts except for the end parts.

Description

DRIVING ELECTRODE PATTERN, TOUCH PANEL, TOUCH PANEL MODULE, AND ELECTRONIC DEVICE INCLUDING THE SAME

The present disclosure relates to a driving electrode pattern, a touch panel, and a touch panel module for a capacitive touch input device, and an electronic device using same.

A touch input device is referred to as an input device for sensing a touch position of a finger on a touch panel and providing information on the sensed touch position as input information. There are several methods used for touch input devices, and representative examples include the resistance method and the capacitive method. The capacitive method mainly includes the self capacitive method and the mutual capacitive method.

The mutual capacitive method includes an operating pattern and a sensing pattern formed of a transparent conductive material, and a capacitance may be formed between the two patterns. If a finger is put near the two patterns or touches them, a capacitance value between the operating and sensing patterns is changed. Accordingly, if a measurement is taken on whether a capacitance value between the two patterns is changed, a confirmation is made on whether a touch panel is touched by a finger. For this confirmation, once an electrical signal is applied to the operating pattern, charges are injected into the sensing pattern. Since the amount of injected charges may vary according to a capacitance value between the two patterns, a change in the capacitance may be detected by measuring the amount of injected charges. As a result, whether a touch input is made is detected.

The touch panel including the operating pattern and the sensing pattern may be used together with a display device such as a liquid crystal display (LCD) device. The display device includes a plurality of display unit pixels, each including three sub pixels for RGB. Since driving voltage and current are applied to each display unit pixel of the display device, another electronic device may be affected by an electric field and magnetic field formed by such a driving voltage and current. That is, the display device may input noise if it is disposed too close to the touch panel.

The present disclosure is to provide a technique related to a pattern of a touch electrode configured to allow a signal inputted to a touch input sensing circuit of a capacitive touch input device to have a high signal to noise ratio. The scope of the present invention is not restricted only by this technical problem.

In accordance with an exemplary embodiment, a touch panel includes: at least one driving electrode extending in a first direction; and a sensing electrode extending in a different direction than the first direction, wherein one of the at least one driving electrode includes a plurality of sub electrodes extending in the first direction and disposed in parallel; end parts at one side of the plurality of sub electrodes are directly connected to each other; and the plurality of sub electrodes are spaced from each other by a predetermined size of a gap at other parts except for the end parts.

End parts at the other side of the plurality of sub electrodes may be directly connected to each other; and the plurality of sub electrodes may be spaced from each other by a predetermined size of a gap in other parts except for the end parts.

The size of a first gap between a first sub electrode and a second sub electrode may be different from that of a second gap between a third sub electrode and a fourth electrode, among the plurality of sub electrodes.

The size of a first gap between a first sub electrode and a second sub electrode may be different from that of a second gap between the second sub electrode and a third sub electrode, among the plurality of sub electrodes.

In accordance with another exemplary embodiment, a driving electrode pattern intersecting a sensing electrode to form a touch panel includes: a plurality of sub electrodes extending in a different direction than an extension direction of the sensing electrode and disposed in parallel, wherein one of the at least one driving electrode includes a plurality of sub electrodes extending in the first direction and disposed in parallel; end parts at one side of the plurality of sub electrodes are directly connected to each other; and the plurality of sub electrodes are spaced from each other by a predetermined size of a gap at other parts except for the end parts.

In accordance with yet another exemplary embodiment, a touch panel module includes: the touch panel; and a touch panel controlling device configured to drive the at least one driving electrode and receive a touch input signal from the sensing electrode.

In accordance with still another exemplary embodiment, an electronic device includes: the touch panel; a touch panel controlling device configured to drive the at least one driving electrode and receive a touch input signal from the sensing electrode; a processor configured to receive the touch input signal from the touch panel controlling device and process at least one program; and a touch screen display configured to output a result of the program processed by the processor.

The present disclosure provides a technique related to a pattern of a touch electrode configured to allow a signal inputted to a touch input sensing circuit of a capacitive touch input device to have a high signal to noise ratio.

Exemplary embodiments can be understood in more detail from the following description taken in conjunction with the accompanying drawings, in which:

Figure 1 is a view illustrating an electronic device using a conductor pattern according to an embodiment;

Figures 2A to 2C are views of a touch panel of Figure 1;

Figures 3A to 3D are views illustrating a driving electrode and a sensing electrode of a touch panel according to an embodiment;

Figures 4A to 4F are views illustrating the shape of one driving electrode according to an embodiment;

Figure 5A is a view illustrating touch panel pixels on one driving electrode formed according to an embodiment;

Figure 5B is a view of one touch panel pixel formed when one driving electrode and one sensing electrode intersect each other;

Figures 7A to 7K are other views illustrating characteristics that noise occurring from a display unit pixel is propagated in a touch panel according to an embodiment; and

Figures 8A and 8B are plan views illustrating a driving electrode and a sensing electrode of a touch panel according to a comparative example; and

Figures 9A to 9K are views illustrating characteristics that noise occurring from a display unit pixel is propagated in a touch panel according to a comparative example.

Exemplary embodiments of the inventive concept will be described below in more detail with reference to the accompanying drawings. The inventive concept may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. In the drawings, the dimensions of layers and regions are exaggerated for clarity of illustration.

Figure 1 is a view illustrating an electronic device using a conductor pattern according to an embodiment.

The electronic device 100 may receive an input signal through a touch panel 1. The touch panel 1 may be formed including a substrate that has a matrix-shaped electrode pattern. The electronic device 100 may include the touch panel 1 for delivering a touch input signal, a touch panel controlling device 3 for outputting a signal for driving the touch panel 1 and receiving an input signal from the touch panel 1, a voltage driver 2 for receiving a touch panel driving signal from the touch panel controlling device 3 to generate a touch panel driving voltage, a main processor 4 for receiving a touch input signal from the touch panel controlling device 3 to execute a program stored in a storage device 5, the storage device 5 for storing at least one program executed according to a touch input signal, and a display device 6 for outputting a processed result of the main processor 4. The display device 6 may overlap the touch panel 1.

The touch panel controlling device 3 may include a touch sensing unit for sensing a signal inputted from the touch panel 1, a panel driving unit for generating a touch panel driving signal to deliver an input signal to the touch panel 2, and a touch panel processor for controlling them. The touch panel processor may be a reprogrammable processor, or a processor operated by a dedicated logic such as a state machine.

Other than that, although not shown in the drawings, the electronic device 100 may include a RAM or another type of a storage device, and may further include another device such as a watchdog.

Figure 2A is a detailed view of the touch panel 1 shown in Figure 1.

The touch panel 1 may include a plurality of transparent electrodes C1 to CM extending in a first direction, for example, a vertical direction, and a plurality of transparent electrodes R1 to RN extending in a second direction, for example, a parallel direction. Here, the first direction may be perpendicular to the second direction, but is not limited thereto. In this specification, for convenience of description, an electrode in a vertical direction may be called as a column electrode or a sensing electrode 20, and an electrode in a parallel direction may be called as a row electrode or a driving electrode 10. The sensing electrodes 20 and the driving electrodes 10 intersect each other, and an intersection point or a region around it may be called as a pixel 15.

Stray capacity Cstray may exist in each pixel 15, which is a capacitance between components, between wirings, and between wirings, elements, and a substrate. Since the stray capacity serves as a condenser in a high frequency circuit or a pulse circuit, it may affect an operation.

Once voltage is applied to the driving electrode 10, electrons may be injected into the sensing electrode 20 through a mutual capacitance Csense at the intersection points of the driving electrodes 10 and the sensing electrodes 20. Charges Qsense inputted to each sensing electrode 20 may be represented with the multiplication of a first level Vdrive of a driving signal and a mutual capacitance Csense (that is, Qsense = Vdrive * Csense).

The touch panel 1 may be formed with a multilayer structure, and the driving electrode 10 and the sensing electrode 20 may be formed on different layers or the same layer. Figures 2B and 2C are views of when the driving electrode 10 and the sensing electrode 20 are formed on different layers. Figures 2D and 2E are views of when the driving electrode 10 and the sensing electrode 20 are formed on the same layer. An insulation layer may be provided between the sensing electrodes 20 and the driving electrodes 20 in order to prevent a short circuit therebetween. A protection layer 30 may be formed on the sensing electrode 20 and the driving electrode 10. Once voltage is applied to the driving electrode 10, an electric field 510 is formed, flowing from the driving electrode 10 toward the sensing electrode 20. According to the amount of the electric field 510, a value of a mutual capacitance Csense between the driving electrode 10 and the sensing electrode 20 may be determined. Once a touch input by a finger 600 is made as shown in Figure 2C or 2E, a part of the electric field 510 flowing from the driving electrode 10 is cut off, so that a mutual capacitance value between the driving electrode 10 and the sensing electrode 20 may be changed (Csense → Csense - ΔCsense).

Referring to Figure 2A again, a driving signal such as a pulse train in which a voltage Vdrive of a first level and a 0 V voltage of a second level are periodically repeated during a specific time interval may be applied to one (i.e., R1 of Figure 2A) of the driving electrodes 10. After the specific time interval, the driving electrode 10 to which a driving signal is inputted may be changed. DC voltage, for example, 0 V, may be applied to the remaining driving electrodes 10 except the driving electrode 10 to which the driving signal is inputted. A circuit, which is formed including the sensing electrode 20, a sensing circuit connected to each sensing electrode 20, and the driving electrode 10, may include resistance and capacitance components. At this point, a time constant may be determined by the multiplication of values of resistance and capacitance components in a part of or entire circuit. Lowering a value of the time constant may shortened the period of a pulse train inputted to the circuit.

Figure 3A is a plan view illustrating a driving electrode 10 and a sensing electrode 20 of a touch panel according to an embodiment.

A total of ten driving electrodes 10 extend in the x-axis direction, and a total of seven sensing electrodes 20 extend in the y-axis direction, but the present invention is not limited to the number of electrodes. Additionally, the x-axis does not have to be exactly orthogonal to the y-axis. The driving electrode 10 and the sensing electrode 20 may be formed of a transparent conductive material at least in a visible ray region. However, as shown in Figure 3A, in order to represent a relative position of the driving electrode 10 and the sensing electrode 20, the driving electrode 10 and the sensing electrode 20 have different shades, and the driving electrode 10 is covered by the sensing electrode 20. This is for convenience of description.

Figure 3A is a view of the touch panel 1 of Figure 2C, seen from the sensing electrode 20 toward the direction of the driving electrode 10, and Figure 3B is a view of the touch panel 1 of Figure 2C, seen from the driving electrode 10 toward the direction of the sensing electrode 20.

Figures 3C and 3D are views of the driving electrode 10 and the sensing electrode 20, respectively.

Figure 4A is a view illustrating a pattern of one driving electrode 10 according to an embodiment. The driving electrode 10 includes nine sub electrodes disposed adjacent and parallel to each other in the y-direction, and the nine sub electrodes are connected to each other at the both end parts of the driving electrode 10. Although one driving electrode 10 including nine sub electrodes is shown in Figure 4A, the number of sub electrodes may vary according to an embodiment. In order to describe this in more detail, Figures 4B and 4C are enlarged views of the both

end parts

11 and 12, respectively.

Referring to Figure 4B, the nine sub electrodes 111 are connected to each other through the first end part 11 of the driving electrode 10. There are eight gaps 112 between the sub electrodes 111. According to an embodiment, the size of each of the eight gaps 112 may be the same, but according to another embodiment, the sizes of the eight gaps 112 may be different. Additionally, according to an embodiment, the width of each of the nine sub electrodes 111 may be the same, but according to another embodiment, the widths of the nine sub electrodes 111 may be different. That is, the shape of the driving electrode 10 according to an embodiment of the present invention is not limited to a size ratio of the width of each sub electrode 111 and a size ratio of the gap 112 between each sub electrodes 111.

Figure 4C is an enlarged view of a second end part 12 of the driving electrode 10 according to an embodiment, and like the first end part 11, the nine sub electrodes 111 are connected to each other.

Although the sub electrodes 111 are connected to each other at the both

end parts

11 and 12 of the driving electrode 10 as shown in Figures 4A to 4C, according to another embodiment, only the one end part 10 of the driving electrode 10 may be used for connection as shown in Figure 4D. At this point, a driving voltage may be supplied to the driving electrode 10 through the one end part 10.

Although the gap 112 between the sub electrodes 111 has a predetermined constant size as shown in Figures 4A to 4D, according to an embodiment, a plurality of gaps 112_1 and 112_2 in one driving electrode 10 may have different sizes as shown in Figure 4E.

Although each sub electrode 111 has the same width as shown in Figures 4A to 4E, according to an embodiment, a plurality of sub electrodes 111_1 and 111_2 in one driving electrode 10 may have different widths as shown in Figure 4F.

Figure 5A is a view illustrating touch panel pixels on one driving electrode formed according to an embodiment. Referring to Figure 5A, since one driving electrode 10 intersects a total of seven sensing electrodes 20, seven touch panel pixels may be formed. Here, the touch panel pixel means the intersection point of the driving electrode 10 and the sensing electrode 20.

Figure 5B is a view of one touch panel pixel formed when one driving electrode 10 and one sensing electrode 20 intersect each other. The horizontal and vertical basic dimension of one touch panel pixel may be represented with [H, V]. A display device may be disposed at one lateral side of the touch panel, and the size of a display unit pixel in the display device may be considerably smaller than that of the above-mentioned touch panel pixel. Accordingly, the basic dimension of one touch panel pixel may correspond to a plurality of display unit pixels. For example, one touch panel pixel may include fifty display unit pixels in horizontal and vertical directions, and each display unit pixel may include three color pixels of RGB. Since different electrical signals may be inputted to each display unit pixel, the each display unit pixel may serve as an independent noise source to the touch panel.

Hereinafter, the reason that a signal to noise ratio of a signal inputted to a touch input sensing unit of a capacitive touch input device is improved by an electrode structure according to an embodiment will be described.

Figures 6A to 6K are views illustrating characteristics that noise occurring from a display unit pixel is propagated in a touch panel according to an embodiment.

Referring to Figure 6A, a pulse train having a voltage of 0 V and a voltage of Vdrive periodically is applied to the driving electrode 10. At this point, when it is assumed that impulse noise occurs at the timing t1 in a display unit pixel corresponding to a point E, effects that the noise affects points A to I on the driving electrode 10 will be described below.

Figure 6B is a view of when a voltage is applied to the driving electrode 10 over time. Figures 6C to 6K are views illustrating voltages at the points A to I on the driving electrode 10, respectively. Since the point E on the driving electrode 10 is the most adjacent to the display unit pixel where the impulse noise occurs, a voltage at the timing t1 is higher than Vdrive (refer to Figure 6G) (provided that it is assumed that the impulse noise has a positive (+) value). Additionally, the points D and F on the driving electrode 10 may have a higher voltage than Vdrive right after the timing t1 because noise is propagated from the point E on the driving electrode 10 (refer to Figures 6F and 6H). However, the points A, B, C, G, H, and I on the driving electrode 10 are separated by the gap 112 from the point E on the driving electrode 10. Additionally, the noise occurring at the point E on the driving electrode 10 is progressively reduced along a sub substrate because each sub electrode of the driving electrode 10 has a resistance component. Accordingly, the points A, B, C, G, H, and I on the driving electrode 10 are almost not affected by the noise from the point E on the driving electrode 10, and since the points A, B, C, G, H, and I on the driving electrode 10 are far from a display unit pixel where the impulse noise occurs, they are not directly affected by the noise occurring from the display unit pixel. Accordingly, the points A, B, C, G, H, and I on the driving electrode 10 have the same voltage waveform as the pulse train applied to the driving electrode 10.

Figures 7A to 7K are other views illustrating characteristics that noise occurring from a display unit pixel is propagated in a touch panel according to an embodiment.

Referring to Figure 7A, a pulse train having a voltage of 0 V and a voltage of Vdrive periodically is applied to the driving electrode 10. At this point, when it is assumed that impulse noise occurs at the timing t1 in a display unit pixel corresponding to a point N, effects that the noise affects points A to I on the driving electrode 10 will be described below.

Figure 7B is a view of when a voltage is applied to the driving electrode 10 over time. Figures 7C to 7K are views illustrating voltages at the points A to I on the driving electrode 10, respectively. Since the point N on the driving electrode 10 is the most adjacent to the display unit pixel where the impulse noise occurs, a voltage at the timing t1 may be higher than Vdrive (not shown). Additionally, the points D, E, and F on the driving electrode 10 may have a higher voltage than Vdrive right after the timing t1 because noise is propagated from the point N on the driving electrode 10 (refer to Figures 6F, 6G, and 6H). However, the points A, B, C, G, H, and I on the driving electrode 10 are separated by the gap 112 from the points N, D, E, and F on the driving electrode 10. Additionally, the noise occurring at the points N, D, E, and F on the driving electrode 10 progressively disappears along a sub substrate because each sub electrode of the driving electrode 10 has a resistance component. Accordingly, the points A, B, C, G, H, and I on the driving electrode 10 are almost not affected by the noise from the points N, D, E, and F on the driving electrode 10, and since the points A, B, C, G, H, and I on the driving electrode 10 are far from a display unit pixel where the impulse noise occurs, they are not directly affected by the noise occurring from the display unit pixel. Accordingly, the points A, B, C, G, H, and I on the driving electrode 10 have the same voltage waveform as the pulse train applied to the driving electrode 10.

Figure 8A is a plan view illustrating the driving electrode 13 and the sensing electrode 20 of a touch panel according to a comparative example.

As shown in Figure 8A, a total of ten driving electrodes 10 extend in the x-axis direction, and a total of seven sensing electrodes 20 extend in the y-axis direction. The driving electrode 13 and the sensing electrode 20 may be formed of a transparent conductive material at least in a visible ray region. However, as shown in Figure 8A, in order to represent a relative position of the driving electrode 13 and the sensing electrode 20, the driving electrode 13 and the sensing electrode 20 have different shades, and the driving electrode 13 is covered by the sensing electrode 20. This is for convenience of description.

Figure 8B is a view of only the driving electrode 13. The driving electrode 13 has a rectangular plate shape.

Referring to Figure 9A, a pulse train having a voltage of 0 V and a voltage of Vdrive periodically is applied to the driving electrode 13. At this point, when it is assumed that impulse noise occurs at the timing t1 in a display unit pixel corresponding to a point E, effects that the noise affects points A to I on the driving electrode 13 will be described below.

Figure 9B is a view of when a voltage is applied to the driving electrode 13 over time. Figures 9C to 9K are views illustrating voltages at the points A to I on the driving electrode 13, respectively. Since the point E on the driving electrode 13 is the most adjacent to the display unit pixel where the impulse noise occurs, a voltage at the timing t1 is higher than Vdrive (refer to Figure 9G). Additionally, the points A, B, C, D, F, G, H, and I on the driving electrode 13 may have a higher voltage than Vdrive right after the timing t1 because noise is propagated from the point E on the driving electrode 13 (refer to Figures 9B to 9F and 9H to 9K). Although the points A, B, C, D, F, G, H, and I on the driving electrode 13 are relatively far from the display unit pixel where impulse noise occurs, they are connected to each other being adjacent to the point E on the driving electrode 13, and therefore are affected by the noise.

When the embodiment is compared with the comparative example, compared to the pixel X1 of Figure 7A according to the embodiment, the pixel X2 of Figure 9A according to the comparative example has a broader area where is affected by the noise from the display unit pixel occurring near the pixel X2. Accordingly, when the pattern according to the embodiment is used, it is understood that a signal inputted to a touch input sensing unit of a capacitive touch input device has a higher signal to noise ratio.

In the description regarding Figures 6B to 6K and Figures 9B to 9K, the impulse noise has a positive (+) value, but when the impulse noise has a negative (-) value, it may be described in a similar way.

Hereinafter, a touch pattern according to an embodiment will be described with reference to Figures 3A, 4A, and 4B. The touch panel 1 may include at least one driving electrode 10 extending in a first direction (e.g., an x direction) and at least one sensing electrode 20 extending in another direction (e.g., a y direction). At this point, one of at least one driving electrode 10 includes a plurality of sub electrodes 111 extending a first direction (e.g., an x direction) being disposed in parallel, and the plurality of sub electrodes 111 are directly connected to each other at the end part 11 of one side. Additionally, the plurality of sub electrodes 111 may be spaced from each other by a predetermined size of the gap 112 at other parts except for the ending part 11 of the one side.

Hereinafter, a pattern of a driving electrode according to another embodiment will be described with reference to Figures 3A, 4A, and 4B. The pattern of the driving electrode 10 is disposed intersecting the sensing electrode 20 to form the touch panel 1. The pattern of the driving electrode 10 includes the plurality of sub electrodes 111 that extend in a different direction (e.g., the x direction) than an extension direction (e.g., the y direction) of the sensing electrode 20 and are disposed in parallel. At this point, the plurality of sub electrodes 111 are directly connected to each other at the end part 11 of one side. Additionally, the plurality of sub electrodes 111 may be spaced from each other by a predetermined size of the gap 112 at other parts except for the ending part 11 of the one side.

The present invention is not limited to a specific pattern of the sensing electrode 20. According to an embodiment, the patter of the sensing electrode 20 may be diversely modified.

According to an embodiment, provided is a technique related to a pattern of a touch electrode configured to allow a signal inputted to a touch input sensing circuit of a capacitive touch input device to have a high signal to noise ratio.

Although the driving electrode pattern, the touch panel, the touch panel module, and the electronic device have been described with reference to the specific embodiments, they are not limited thereto. Therefore, it will be readily understood by those skilled in the art that various modifications and changes can be made thereto without departing from the spirit and scope of the present invention defined by the appended claims.

Claims

A touch panel comprising:

at least one driving electrode extending in a first direction; and

a sensing electrode extending in a different direction than the first direction,

wherein one of the at least one driving electrode comprises a plurality of sub electrodes extending in the first direction and disposed in parallel;

end parts at one side of the plurality of sub electrodes are directly connected to each other; and

the plurality of sub electrodes are spaced from each other by a predetermined size of a gap at other parts except for the end parts.
The touch panel of claim 1, wherein end parts at the other side of the plurality of sub electrodes are directly connected to each other; and

the plurality of sub electrodes are spaced from each other by a predetermined size of a gap in other parts except for the end parts at the one side and the end parts at the other side.
The touch panel of claim 1, wherein the size of a first gap between a first sub electrode and a second sub electrode is different from that of a second gap between a third sub electrode and a fourth electrode, among the plurality of sub electrodes.
The touch panel of claim 1, wherein the size of a first gap between a first sub electrode and a second sub electrode is different from that of a second gap between the second sub electrode and a third sub electrode.
A pattern of a driving electrode intersecting a sensing electrode to form a touch panel, comprising:

a plurality of sub electrodes disposed in parallel and extending in a different direction than an extension direction of the sensing electrode,

end parts at one side of the plurality of sub electrodes are directly connected to each other; and

the plurality of sub electrodes are spaced from each other by a predetermined size of a gap at other parts except for the end parts.
The driving electrode pattern of claim 5, wherein end parts at the other side of the plurality of sub electrodes are directly connected to each other; and

the plurality of sub electrodes are spaced from each other by a predetermined size of a gap in other parts except for the end parts at the one side and the end parts at the other side.
A touch panel module comprising:

the touch panel of any one of claims 1 to 4; and

a touch panel controlling device configured to drive the at least one driving electrode and receive a touch input signal from the sensing electrode.
An electronic device comprising:

the touch panel of any one of claims 1 to 4;

a touch panel controlling device configured to drive the at least one driving electrode and receive a touch input signal from the sensing electrode;

a processor configured to receive the touch input signal from the touch panel controlling device and process at least one program; and

a touch screen display configured to output a result of the program processed by the processor.