Patent Application
20170060333
The present invention relates to a capacitive touch panel and, more particularly, to a capacitive touch panel that can reduce the total resistance value of top transparent electrodes, that can reduce the number of electrode terminals used for the top transparent electrodes, and that can provide the accurate coordinate values of a touched location through the guarantee of coordinate linearity.
Personal computers (PCs), portable transmission devices, and other personal dedicated information processing devices perform text and graphics processing and the like via various input devices, such as a keyboard, a mouse, and a digitizer.
Input devices including only a keyboard and a mouse cannot deal with the extended uses of products, such as PCs, as input devices used for interfaces. Accordingly, there has been a need for an input device that is simpler than a conventional keyboard and mouse, that can reduce erroneous manipulations, that enables anyone to easily perform input operations, and that enables characters to be entered by a hand while it is being carried. In particular, a touch panel is known as an input device that is simple, that reduces erroneous manipulations, that enables anyone to perform input operations while carrying the input device, and that enables characters to be entered without another input device. The detection method, structure and performance thereof are well known.
Such touch panels include: resistive touch panels (screen) in which two sheets having respective resistance components that are disposed such that they are separated by a spacer and are brought into contact with each other by pressing have been combined with each other; capacitance touch panels in which current continuously flows along the surface of a panel and electrons flowing along liquid crystals are attracted to a contact point when a finger or conductor comes into contact with a screen, thereby achieving recognition; Surface Acoustic Wave (SAW) touch panels; optical (infrared) sensor touch panels; and electromagnetic touch panels.
Resistive touch panels are configured in a form in which a plurality of films (screens) is stacked on top of each other on liquid crystals. Resistive touch panels include a film disposed on the outermost side (a portion with which a hand or pen comes into contact) and made of material that is soft and robust to scratches, a film configured to mitigate impacts, and two transparent conductive films (thin transparent conductive substrates) configured to detect input, which are sequentially superimposed on top of each other.
Accordingly, resistive touch panels enable a screen to be touched with not only a finger but also a stylus pen (a touch pen) and almost all objects that can be held in a hand of a user, and are advantageous for successive handwriting inputs or small icon touches. Since the manufacturing costs of resistive touch panels are inexpensive because the principle thereof is simple, resistive touch panels are the most widely applied touch panels. Principal devices employing resistive touch panels include portable game consoles, such as the Nintendo DS, and mobile phones, such as Samsung Anycall Haptic phones and LG Cyon Cooky phones. These devices support handwriting input method-based games, or provide neat user interfaces.
Capacitive touch panels are based on a method using static electricity that is present in the human body. That is, current is made to continuously flow along liquid crystal glass by coating the liquid crystal glass with a conductive compound, and electrons flowing on the liquid crystal glass are attracted to a contact point when a finger comes into contact with a screen. Then, sensors present at corners of the touch screen detect the electrons and thus identify an input.
Accordingly, capacitive touch panels enable touch input to be performed even by slightly grazing a screen (which presents emotional sensations), and support multi-touch functionality (which enables the concurrent recognition of a plurality of contact points). Furthermore, since the liquid crystal glass coated with a dielectric (a conductive compound) is used, there is no concern about a reduction in image quality. Principal devices employing capacitive touch panels include most smart phones that have been recently released.
The capacitance input method of capacitive touch panels is appropriate for the application of effective user interfaces to small screens, such as those of the above products. Recently, tablet PCs (such as the Samsung Galaxy Tab, the Apple iPad, etc.) equipped with screens larger than those of mobile phones have attracted attention. Most of these tablet PCs employ capacitance touch screens rather than resistive touch screens.
As shown in
The plurality of bottom transparent electrodes 110 may be each formed linearly in a first direction, for example, a lateral direction, and may be formed on a lower transparent substrate (not shown).
In this case, the plurality of bottom transparent electrodes 110 may be disposed at predetermined intervals in a second direction, for example, a vertical direction.
The plurality of top transparent electrodes 120 is formed in a direction perpendicular to the plurality of bottom transparent electrodes 110. That is, the plurality of top transparent electrodes 120 is formed in the second direction perpendicular to the first direction.
In this case, the plurality of top transparent electrodes 120 may be formed on an upper transparent substrate (not shown).
In the conventional capacitive touch panel configured as described above, a mutual capacitance value is generated between the bottom transparent electrode 110 and the top transparent electrode 120 at each point where the electrodes intersect each other. When the human body comes into contact with or approaches the point, part of the mutual capacitance value generated at the intersection point is transferred to the human body due to the virtual ground phenomenon of the human body. In this case, the mutual capacitance value is reduced at the intersection point, and the recognition of contact with the human body and coordinate calculation are performed based on the change in mutual capacitance.
In the conventional capacitive touch panel, the top transparent electrodes 120 are arranged at intervals of about 5 mm based on a diameter ranging from 5 to 6 mm, which corresponds to a human body contact area. The top transparent electrodes 120 may be arranged at intervals of a maximum of 6.5 mm based on the material and thickness of the cover.
However, when the number of electrodes or electrode terminals available in the structure of the conventional capacitive touch panel is insufficient, the electrodes are arranged at wider intervals, for example, intervals of 10 mm. In this case, a problem arises in that it becomes difficult to identify contact with the human body, with the result that it becomes difficult to calculate accurate coordinates. That is, the electrode structure of the conventional capacitive touch panel has a problem in that it cannot guarantee coordinate linearity.
Therefore, there is a need for a touch panel that can guarantee coordinate linearity even when the number of available electrodes is insufficient and thus can provide the accurate coordinate values of a touched location.
Accordingly, the present invention has been made to solve the above problems occurring in the conventional technology, and an object of the present invention is to provide a capacitive touch panel that reduces the total resistance value of top transparent electrodes, thereby enhancing response speed and touch sensitivity.
More specifically, the present invention is intended to provide a capacitive touch panel in which each top transparent electrode is configured to include a linear electrode linearly formed and pattern electrodes formed on the left and right sides of the linear electrode at predetermined intervals in an alternately protruding and recessed form, thereby reducing the total resistance value of top transparent electrodes.
Another object of the present invention is to provide a capacitive touch panel that can guarantee coordinate linearity even when the number of electrode terminals is small and thus can provide the accurate coordinate values of a touched location.
Still another object of the present invention is to provide a capacitive touch panel that can reduce the number of electrode terminals, thereby reducing manufacturing costs and also improving the manufacturing yield of products.
In accordance with an aspect of the present invention, there is provided a capacitive touch panel including a plurality of bottom transparent electrodes formed in a first direction and a plurality of top transparent electrodes formed in a second direction perpendicular to the first direction, wherein each of the top transparent electrodes includes: a linear electrode configured to have a predetermined width, and linearly formed in the second direction; a plurality of first pattern electrodes formed on the first side of the linear electrode with respect to the first direction in a predetermined first pattern, and formed at predetermined intervals in an alternately protruding and recessed form in the second direction; and a plurality of second pattern electrodes formed on the second side of the linear electrode with respect to the first direction in a predetermined second pattern, and formed at predetermined intervals in an alternately protruding and recessed form in the second direction.
The first pattern electrodes may be disposed alternately with the second pattern electrodes of an top transparent electrode neighboring the first side.
The first pattern electrodes and the second pattern electrodes may be formed to be symmetrical with respect to the linear electrode.
Each of the plurality of first pattern electrodes and the plurality of second pattern electrodes may include: a first pattern linear electrode configured such that one side thereof is connected to the linear electrode; and a second pattern linear electrode configured such that one side thereof is connected to the other side of the first pattern linear electrode and the other side thereof is connected to the linear electrode.
Each of the plurality of first pattern electrodes and the plurality of second pattern electrodes may include: a first pattern linear electrode configured such that one side thereof is connected to the linear electrode; and a second pattern linear electrode configured such that one side thereof is connected to the other side of the first pattern linear electrode and the other side thereof is formed to be floated.
The first pattern electrodes and the second pattern electrodes may be formed to be symmetrical with respect to the center point of the linear electrode.
The first pattern electrodes and the second pattern electrodes may be “V” shaped patterns in the first direction.
The length of the first pattern electrodes and the second pattern electrodes formed in the first direction may be determined by considering at least one of the sensitivity of the touch panel, the total resistance value of the electrodes, and the number of terminals for the top transparent electrodes.
The first pattern electrodes and the second pattern electrodes may be formed at aligned or interleaved locations in the second direction.
The bottom transparent electrodes may be linearly formed in the first direction.
The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
Embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, detailed descriptions of related well-known components or functions that may unnecessarily make the gist of the present invention obscure will be omitted.
The prevent invention is not limited to the embodiments. Throughout the accompanying drawings, the same reference symbols are assigned to the same components.
A capacitive touch panel according to an embodiment of the present invention is described in detail below with reference to
The gist of the present invention resides in providing coordinate linearity even when the number of electrodes is small and thus providing the accurate coordinate values of a touched location, and also resides in reducing the total resistance value of electrodes, increasing a change in mutual capacitance attributable to a touch and thus improving response speed and touch sensitivity.
Referring to
The plurality of bottom transparent electrodes 210 is linearly formed in a first direction, for example, a lateral direction (an x axis direction). Alternatively, the plurality of bottom transparent electrodes 210 may be disposed at predetermined intervals in a second direction, for example, a vertical direction (a y axis direction).
The plurality of bottom transparent electrodes 210 functions to prevent electromagnetic waves (noise) from being transferred to the top transparent electrodes 220 by blocking electromagnetic waves radiated by a display screen that is present below the bottom transparent electrodes 210.
In this case, the plurality of bottom transparent electrodes 210 may be formed on a lower transparent substrate (not shown).
The plurality of bottom transparent electrodes 210 is electrically connected to the predetermined terminals 230 for bottom transparent electrodes, and may be connected to a control module (not shown) for detecting touched coordinate locations via the terminals 230 for bottom transparent electrodes.
The plurality of top transparent electrodes 220 is formed in a direction perpendicular to the bottom transparent electrodes 210. That is, the plurality of top transparent electrodes 220 is formed in the second direction, for example, the vertical direction, perpendicular to the first direction in which the bottom transparent electrodes 220 are formed. Alternatively, the plurality of top transparent electrodes 220 may be disposed at predetermined intervals in the first direction, for example, the lateral direction.
The top transparent electrodes 220 are configured to be spaced apart from the bottom transparent electrodes 210 by a predetermined interval, and are electrically connected to the predetermined terminals 240 for top transparent electrodes.
In the same manner, the plurality of top transparent electrodes 220 may be connected to the control module for detecting touched coordinate locations via the predetermined terminals 240 for top transparent electrodes.
In this case, the plurality of top transparent electrodes 220 may be formed on an upper transparent substrate.
As shown in
The first pattern electrodes 222a and 222c and the second pattern electrodes 223a and 223b shown in
The first electrode patterns 222a or 222c are disposed alternately with the second pattern electrodes 223b or 223a of an top transparent electrode 220b or 220a neighboring the first side, i.e., the left side, and the second pattern electrodes 223a or 223b are disposed alternately with the first pattern electrodes 222a or 222c of an top transparent electrode 220a or 220c neighboring the second side, i.e., the right side.
That is, the first pattern electrodes 222a of the first top transparent electrode 220a are disposed alternately with the second pattern electrodes 223b of the second top transparent electrode 220b, and the second pattern electrodes 223a of the first top transparent electrode 220a are disposed alternately with the first pattern electrodes 222c of the third top transparent electrode 220c.
The first pattern electrodes 222a and 222c and the second pattern electrodes 223a and 223b shown in
Moreover, the leftmost and rightmost top transparent electrodes of the top transparent electrodes according to the present embodiment may have left or right side pattern electrodes that are formed in different shapes that fit regions where the electrodes are formed, as shown in
As described above, in the capacitive touch panel according to the present embodiment, each of the top transparent electrodes may include the “V”-shaped pattern electrodes that are connected to the linear electrode and are formed in the first direction. It will be apparent that the pattern electrodes of the present invention are not limited to the “V”-shaped pattern electrodes but may include all type of pattern electrodes as long as the pattern electrodes of each top transparent electrode are disposed alternately with those of a neighboring top transparent electrode.
Furthermore, the first pattern electrodes and the second pattern electrodes may be formed to a predetermined length in the first direction. In this case, the length of the pattern electrodes may be determined by considering at least one of the sensitivity of the touch panel, the total resistance value of the electrodes, and the number of terminals for the top transparent electrodes. Furthermore, the pattern of the pattern electrodes may be also determined by considering the sensitivity, the total resistance value of the electrodes and the like.
As shown in
In contrast, in the capacitive touch panel of the present invention, a mutual capacitance value generated between a bottom transparent electrode 210 and an top transparent electrode 220 is generated via various paths compared to that of the conventional touch panel. That is, a mutual capacitance value is generated between the bottom transparent electrode 210 and the linear electrode 221, between the bottom transparent electrode 210 and a first pattern electrode 222, and between the bottom transparent electrode 210 and a second pattern electrode 223. Accordingly, the generated mutual capacitance value is large. Furthermore, each of the first pattern electrode 222 and the second pattern electrode 223 is divided into a first pattern linear electrode and a second pattern linear electrode, as described with reference to
Accordingly, a change in mutual capacitance transferred to the human body via a hand of a user during contact with the human body of the user is large and thus sensitivity is enhanced, thereby providing the advantage of easily calculating the coordinate values of a touched portion.
As shown in
In contrast, in the case of the present invention shown in
As shown in
In contrast, as shown in
Referring to
The first pattern electrode 812 shown in
Since the second pattern electrode 813 is formed to be symmetrical to the first pattern electrode 812 with respect to the linear electrode 811, it will be apparent that the second pattern electrode 813 includes the two pattern linear electrodes that constitute the first pattern electrode 812.
The top transparent electrodes shown in
The first pattern electrode 912 and second pattern electrode 913 of the top transparent electrode 910 shown in
In each of the top transparent electrodes 1010, 1110 and 1210 shown in
As an example, as shown in
As another example, as shown in
Although the pattern of the first pattern electrodes has been described as being the same as that of the second pattern electrodes except that they differ only in the location or direction, the present invention is not limited thereto, but may employ different patterns. For example, the first pattern electrodes may be formed in the pattern of the first pattern electrodes of one of
As described above, in the capacitive touch panel according to the present invention, each top transparent electrode is formed to include a linear electrode and two pattern electrodes formed in a direction, for example, the first direction, in which bottom transparent electrodes are formed, thereby reducing the total resistance value of top transparent electrodes and thus increasing the speed of response to a touch. The pattern electrodes are employed on the left and right sides of each linear electrode, thereby providing coordinate linearity through the generation of a large mutual capacitance value even when the number of terminals is small and thus providing the accurate coordinate values of a touched portion using the coordinate linearity.
According to the present invention, each top transparent electrode is configured to include a linear electrode linearly formed and pattern electrodes formed on the left and right sides of the linear electrode at predetermined intervals in an alternately protruding and recessed form, thereby improving response speed through a reduction in the total resistance value of electrodes and also enhancing touch sensitivity through an increase in a mutual capacitance change attributable to a touch.
The present invention is configured such that the pattern electrodes of each top transparent electrode are arranged alternately with those of a neighboring top transparent electrode, and thus can guarantee coordinate linearity even when the number of electrode terminals is small, thereby providing the accurate coordinate values of a touched location.
The present invention can reduce the number of electrode terminals, and thus can reduce the number of ports connected to top transparent electrodes in a control module for detecting touch coordinates, such as a microcontroller (MCU), thereby reducing the manufacturing costs of products and also improving the manufacturing yield of products through a reduction in defect rate.
While the present invention has been described in conjunction with specific details, such as specific configuration elements, and limited embodiments and diagrams above, these are provided merely to help an overall understanding of the present invention, the present invention is not limited to these embodiments, and various modifications and variations can be made based on the above description by those having ordinary knowledge in the art to which the present invention pertains.
Therefore, the technical spirit of the present invention should not be determined based on only the described embodiments, and the following claims, all equivalents to the claims, and equivalent modifications should be construed as falling within the scope of the spirit of the present invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2013-0036324 | Apr 2013 | KR | national |
This application is a continuation of PCT/KR2014/002782 filed on Apr. 1, 2014, which claims priority to Korean Application No. 10-2013-0036324 filed on Apr. 3, 2013, which application is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/KR2014/002782 | Apr 2014 | US |
| Child | 14873351 | US |
