KR101397670B1 - Tactile touch screen apparatus - Google Patents

Abstract

A tactile touch screen device using a capacitive method includes an upper substrate which has upper electrodes formed on; a lower substrate which has lower electrodes formed on a surface facing the upper electrodes; and a contraction/restoration layer which is placed between the upper electrodes and the lower electrodes, and is contracted and restored by the load.

Description

[0001] TACTILE TOUCH SCREEN APPARATUS [0002]

The present invention relates to a touch screen device.

The touch screen device touches a finger or a touch pen, stylus, or the like on the screen to write or draw a picture, and executes an icon to execute a desired command. The touch screen device can detect input by resistive type, capacitive type, optical type and the like.

Referring to FIG. 1, a general capacitive touch screen device includes a diamond-shaped ITO (Indium Tin Oxide) transparent electrode pattern. The electrodes of the touch screen device are composed of a driving line and a sensing line. The touch screen device calculates the coordinates based on the change in the capacitance value of each electrode line by the touch of the conductor and displays the touch position.

Although the capacitive touch screen device of the past can recognize the touch position, it is impossible to recognize the touch load. Conventional capacitive touchscreen devices do not recognize a touch when they touch an object other than a conductor. Also, the conventional touch screen device does not recognize the touch load. When the user strongly touched the touch screen device, the touch screen device responds. However, this is because the contact area of the hand is widened, the variation of the capacitance value becomes larger, and the touch load is not recognized.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a touch screen device for recognizing a touch position and a touch load.

A capacitive tactile touch screen device according to an embodiment of the present invention includes an upper substrate on which an upper electrode is formed, a lower substrate on a surface facing the upper electrode, and a lower substrate between the upper electrode and the lower electrode. And a shrinkage restoration layer which is contracted and restored by a load.

The upper electrode may be formed in a pattern in which open regions for generating fringe capacitance are symmetrical in the up, down, left, and right directions.

The upper electrode may be formed by connecting a plurality of unit patterns, and the open region may be formed in a top, bottom, left, and right symmetry around the unit pattern.

The lower electrode may be formed in a rectangular bar pattern.

The haptic touch screen device may further include a sensing unit for sensing a touch position and a touch load based on a change in the mutual capacitance generated between the upper electrode and the lower electrode.

The sensing unit recognizes a signal having a value smaller than the initial mutual capacitance as a soft touch and a signal having a value larger than the initial mutual capacitance as a hard touch.

The shrinkage restoration layer may be contracted or restored according to the load to change the distance between the upper electrode and the lower electrode.

The haptic touch screen device may further include a sealing structure disposed on the outer side of the shrinkage restoration layer to prevent loss of the shrinkage restoration layer due to deformation and maintain the shape of the shrinkage restoration layer.

According to the embodiment of the present invention, the tactile touch screen device can recognize the touch position and the touch load. According to the embodiment of the present invention, the tactile touch screen device can detect multi-touch and multi-force. According to an embodiment of the present invention, the tactile touch screen device can also operate on the touch of an insulator. In addition, according to the embodiment of the present invention, an upper electrode uniformly formed in an open area on a channel electrode can easily realize a soft touch and a hard touch, and the entire touch screen can be uniformly touched.

FIG. 1 is a view showing a capacitive touch screen device.
2 is a view for explaining a self-capacitance sensing method.
3 and 4 are diagrams for explaining a mutual capacitance sensing method.
5 and 6 are views for explaining the change of the mutual capacitance according to the electrode pattern.
7 and 8, respectively, show a haptic touch screen device in accordance with an embodiment of the present invention.
9 to 12 are views showing electrode patterns according to an embodiment of the present invention.
13 is a diagram showing a circular pattern according to an embodiment of the present invention.
FIG. 14 is a view showing a cross pattern according to an embodiment of the present invention. FIG.
15 is a view for explaining a variation of a mutual capacitance according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

2 is a view for explaining a self-capacitance sensing method.

Referring to FIG. 2, the self-capacitance sensing touch screen device 10 senses the change in capacitance of each line electrode when a conductor such as a finger is touched. The touch screen device 10 recognizes the touch position based on the capacitance change.

The self-capacitance sensing method easily detects touches at one point. However, when a plurality of points are simultaneously touched (multi-touch), the self-capacitance of the driving line and the sensing line connected to each touch point changes. Therefore, a ghost image that is sensed as a touched point may also be generated, and it may be difficult to recognize the accurate touched position.

That is, when the user touches two points 11 and 12 at the same time, the self-capacitance also changes at the other two points 13 and 14 as well. Therefore, the touch screen device 10 has a problem that the four points 11, 12, 13, and 14 are recognized as being touched.

3 and 4 are diagrams for explaining a mutual capacitance sensing method.

Referring to FIG. 3, the touch screen device 20 calculates a touch position by a mutual capacitance sensing method, which is a mutual capacitance between two electrodes.

The mutual capacitance sensing scheme senses the mutual capacitance, the mutual capacitance between the two electrodes. The mutual capacitance is a mutual capacitance formed between two electrodes, and recognizes the touch position by sensing a change in mutual capacitance formed between two electrodes when a conductor such as a finger is touched. Therefore, the mutual capacitance sensing method does not generate a virtual image that may occur in the self capacitance sensing method, so that a plurality of points can be touched simultaneously.

The mutual capacitance is formed by the upper electrode 30 and the lower electrode 40. The mutual capacitance Cm formed by the two electrodes is determined by the parallel plate capacitance Cp formed in the vertical direction at the overlapping portion of the two electrodes and the fringe capacitance , Cf). The mutual capacitance Cm is expressed by Equation (1).

[ Equation 1 ]

Cm = Cp + Cf

In order to recognize the touch position and the touch load by sensing the change of the capacitance due to the touch, the change tendency of the parallel plate capacitance (Cp) and the fringe capacitance (Cf) in the capacitance change of the mutual capacitance (Cm) It is important to make a pattern of. That is, when a user touches or applies a load to the touch screen device, the component that changes in the mutual capacitance Cm may vary not only in a specific component but also in both components. Accordingly, the touch screen device can recognize the touch position and the touch load based on the change of the parallel plate capacitance Cp and the fringe capacitance Cf.

4, in a structure in which a part of the upper electrode 30 is opened with respect to the lower electrode 40, a conductor such as a finger touches the upper electrode 30 to apply a load . Then, the fringe capacitance Cf is absorbed toward the conductor such as the finger, and the mutual capacitance Cm decreases as a whole. Here, the open portion without the upper electrode corresponding to the lower electrode is referred to as an "open area" in the following. The open region forms the pattern of the upper electrode, and the fringe capacitance is created through the open region.

When a conductor such as a finger touches the upper electrode 30 strongly and applies a load, the distance between the upper electrode 30 and the lower electrode 40 becomes closer, and the parallel plate capacitance Cp increases. However, as the static electricity passes out through the finger, the fringe capacitance (Cf) decreases. That is, although the parallel plate capacitance Cp increases, the fringe capacitance Cf decreases, so that the signal processing by the touch is not easy.

By reducing the open area in the upper electrode, the amount of static electricity exiting the electrode is reduced. Therefore, it is possible to reduce the decrease of the fringe capacitance Cf and increase the parallel plate capacitance Cp, thereby improving the touch and touch sensitivity. However, if the open area in the upper electrode is reduced too much, the amount of static electricity, i.e., the amount of fringing capacitance Cf, coming out of the lower electrode is reduced. Therefore, the change of the mutual capacitance Cm is small, and it may be difficult for the soft touch to be recognized.

Further, as the load is increased, the distance between the two electrodes is reduced, and the parallel plate capacitance Cp is increased. In this case, there is no problem in the hard touch, but it may be difficult to recognize the soft touch.

5 and 6 are views for explaining the change of the mutual capacitance according to the electrode pattern.

Referring to FIG. 5, a cross bar electrode crosses the upper electrode and the lower electrode in the form of a bar. In this case, since the open area in the upper electrode pattern is too small, a change in the fringe capacitance Cf is small at the time of soft touch. Therefore, it is difficult to recognize the change of the mutual capacitance (Cm) when the rod cross electrode is soft-touched. However, the bar cross electrode increases the parallel plate capacitance (Cp) upon hard touch. Therefore, the rod cross-shaped electrode can recognize the touch position and the touch load based on the mutual capacitance Cm that varies depending on the parallel plate capacitance Cp. That is, the electrode pattern crossing the bar shape is difficult to recognize the soft touch, but hard touch recognition is possible.

Referring to FIG. 6, the dummy pattern electrode is a structure in which dummy patterns are arranged in an island shape, and the open region is wider than the rod cross electrode. The dummy pattern electrode is more affected by the fringe capacitance (Cf) than the rod cross electrode during soft touch.

In the dummy pattern electrode, an electric field coming out of the open region is absorbed by a finger or the like during soft touch, and the fringe capacitance Cf is greatly decreased. Accordingly, the mutual capacitance Cm of the dummy pattern electrode is instantaneously reduced when soft touch is performed.

When a load is applied to the dummy pattern electrode, the distance between the two electrodes decreases, and the parallel plate capacitance Cp increases. Therefore, when a load is applied to the dummy pattern electrode, the mutual capacitance Cm increases.

However, if the open area in the dummy patterned electrode pattern is too wide, the fringing capacitance Cf may dominate the parallel plate capacitance Cp. Then, if the change of the mutual capacitance Cm is operated at a level lower than the initial mutual capacitance Cm, the mutual capacitance Cm is increased by the increase of the load, or the mutual capacitance Cm) is difficult to distinguish. Also, since the dummy pattern electrode is an electrode pattern which is not uniform in all of the upper, lower, left, and right sides, non-uniformity may occur in the operation of the device.

7 and 8, respectively, show a haptic touch screen device in accordance with an embodiment of the present invention.

7 and 8, the tactile touch screen device 100 may include a touch location (e.g., X, Y coordinates) and a touch load (e.g., depth or Z direction) Lt; / RTI > The haptic touch screen device 100 includes an upper substrate 110, a lower substrate 130 and a shrinkage restoration layer 150 positioned between the upper substrate 110 and the lower substrate 130. The haptic touch screen device 100 may include a sealing structure 170 that seals the shrinkage restoration layer 150. The haptic touch screen device 100 may include a sensing unit 190 that senses a touch position and a touch load based on a change in the mutual capacitance.

An upper electrode 111 and a lower electrode 131 which are transparent electrodes are disposed on the upper substrate 110 and the lower substrate 130, respectively. The upper substrate 110 and the lower substrate 130 may be formed of a material such as Graphene, CNT, ITO (indium tin oxide), PEDOT, Ag nanowire, PANI and the like on a thin transparent material such as PET film or glass And a transparent electrode patterned with the same conductive nano material or the like. The upper electrode 111 and the lower electrode 131 face each other, and the two electrodes form a mutual capacitance. Here, the upper electrode 111 has a symmetrical and uniform pattern of open regions.

The shrinkage restoration layer 150 is a tactile sensing layer that shrinks and restores according to the load. The shrinkage restoration layer 150 is contracted or restored according to the load to change the distance between the upper electrode 111 and the lower electrode 131. Accordingly, the touch screen device 100 can recognize the touch position and the touch load based on the mutual capacitance Cm changed by the load.

Since the shrinkage restoration layer 150 is a region deformed by a touched load, it is formed of a material that is easily shrunk and restored by a load. The shrinkage restoration layer 150 may be formed of various materials such as a transparent silicone gel (silicone gel), silicone oil, air, and a glycerin polymer. At this time, the shrinkage restoration layer 150 may use a high-permittivity material to increase the sensitivity.

The shrinkage restoration layer 150 may be a liquid or sheet type material. When the shrinkage restoration layer 150 is made of a liquid material, a dam (seal) structure 170 may be formed between the upper substrate 110 and the lower substrate 130 to inject a liquid material have. The shrinkage restoration layer 150 is sealed with an epoxy, an adhesive material, rubber or the like so that the injected liquid material does not flow out to the outside.

The shrinkage restoration layer 150 may be manufactured by attaching a sheet between the upper electrode 111 and the lower electrode 131 using a process such as lamination. At this time, the sheet is made of a transparent material.

The sealing structure 170 is installed outside the shrinkage restoration layer 150 to prevent loss of the shrinkage restoration layer 150 due to deformation and maintain the shrinkage restoration layer 150 in a predetermined shape.

The sensing unit 190 senses the touch position and the touch load based on a change in the mutual capacitance Cm generated between the upper electrode 111 and the lower electrode 131. [ The sensing unit 190 recognizes the touch position based on a signal smaller than the initial mutual capacitance Cm and recognizes the touch load based on a signal larger than the initial mutual capacitance Cm.

9 to 12 are views showing electrode patterns according to an embodiment of the present invention.

9, the upper electrodes Y1, Y2, Y3, etc. 111 and the lower electrodes X1, X2, X3, etc. (not shown) of the haptic touch screen device 100 overlap each other. The upper electrode 131 is formed in a pattern in which open regions are formed symmetrically in the up, down, left, and right directions, that is, a uniform pattern as a whole. At this time, the lower electrode may be a rectangular bar pattern.

Referring to FIG. 10, the upper electrode 111 has a pattern in which open regions are formed symmetrically. For example, when the pattern 200 of FIG. 9 is enlarged, the upper electrode 111 is formed of a plurality of connected unit patterns 300. The open region is formed symmetrically around the unit pattern 300. [ Here, the unit pattern may be a square (& squ &). Alternatively, the unit pattern may be a shape capable of designing an open area symmetrically around the periphery, for example, a circle (∘), a diamond (◇), or the like.

Referring to FIGS. 11 and 12, symmetrical open regions formed around the unit pattern 300 may be variously implemented. When the pattern 210 of FIG. 10 is enlarged, the upper electrode may be a transparent electrode pattern in which a C-shaped open region between the electrodes is repeated in left-right symmetry. Alternatively, the upper electrode may be a transparent electrode pattern in which an open region of a square shape or a square shape is repeated between upper and lower electrodes symmetrically.

The spacing of the open areas is determined in consideration of visibility and the like, and it can be adjusted according to the size and usage of the touch screen.

The upper electrode 131 formed with open regions symmetrically in the up, down, left, and right directions includes an open region than the bar cross electrode. Therefore, the upper electrode 131 can increase the signal sensitivity at the time of soft touch. The upper electrode 131 has a larger area where the upper electrode and the lower electrode overlap than the dummy pattern electrode. Therefore, the upper electrode 131 can increase the variation of the parallel plate capacitance Cp due to the load.

FIG. 13 is a view showing a circular pattern according to an embodiment of the present invention, and FIG. 14 is a view showing a cross pattern according to an embodiment of the present invention.

Referring to FIGS. 13 and 14, the haptic touch screen device 100 may be implemented as an electrode in which various patterns are repeatedly formed. For example, the tactile touch screen device 100 may be implemented as an electrode of a pattern having an open area of circle (O) or an electrode of a pattern having an open area of a cross (+). Alternatively, the pattern of the electrodes may be a transparent electrode pattern in which the open regions of a letter shape, a letter shape, a straight shape (-), a square shape (□), a rhombic shape (◇), and a circle shape (○) are repeated symmetrically.

15 is a view for explaining a variation of a mutual capacitance according to an embodiment of the present invention.

Referring to FIG. 15, the haptic touch screen device 100 has an electrode structure that combines the advantages of the rod cross electrode and the dummy pattern electrode. Accordingly, when the touch-sensitive touch screen device 100 is soft-touched, the initial mutual capacitance Cm is reduced by the reduction of the fringe capacitance Cf. The haptic touch screen device 100 can recognize the touch position based on the mutual capacitance Cm reduction signal.

When the tactile touch screen device 100 is hard-touched and the load is applied, the mutual capacitance Cm is gradually increased from the initial value to a value larger than the initial value by the increase of the parallel plate capacitance Cp.

Accordingly, the haptic touch screen device 100 recognizes a signal having a value smaller than the initial mutual capacitance Cm as a soft touch. The haptic touch screen device 100 recognizes a signal having a value larger than the initial mutual capacitance Cm as a signal due to a load, that is, a hard touch.

Thus, the tactile touch screen device 100 can recognize both the soft touch and the hard touch.

In particular, when the tactile touch screen device 100 is touched with a non-conductive material, there is almost no influence due to the fringe capacitance Cf in the mutual capacitance change. The mutual capacitance (Cm) is always increased in accordance with the touch and the touch load. Accordingly, the tactile touch screen device 100 can appropriately adjust the sensitivity of the device so that the touch position and the touch load can be recognized based on a signal that the mutual capacitance Cm increases. That is, the haptic touch screen device 100 may perform various functions by sensing a touch position at a value lower than a predetermined mutual capacitance Cm and a touch load at a value higher than the predetermined mutual capacitance Cm.

 In addition, the tactile touch screen device 100 can exhibit the same and uniform operating characteristics at any position due to the open area uniformly formed in all the regions of the upper electrode. Since the upper electrode 131 is symmetrically opened on the upper surface of the tactile touch screen device 100, when the mutual capacitance Cm is recognized, when the soft touch and the hard touch are performed, the parallel plate capacitance Cp and the fringe Either one of the capacitances Cf does not have a dominant influence.

As described above, according to the embodiment of the present invention, the tactile touch screen device 100 can solve the problem of virtual image generation that may occur in the existing touch screen. The tactile touch screen apparatus 100 can recognize the touch position and the touch load accurately by sensing a change in the mutual capacitance Cm formed by the two electrodes. In addition, according to the embodiment of the present invention, the tactile touch screen device can detect multi-touch and multi-force. In addition, although the conventional touch screen does not respond to the touch of the non-conductive material, the touch screen device 100 can recognize touches of various non-conductive materials such as plastic and wood in addition to conductors such as fingers.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, Of the right.

Claims (8)

A capacitive tactile touch screen device comprising:
An upper substrate on which an upper electrode is formed,
A lower substrate having a lower electrode formed on a surface facing the upper electrode,
A shrinkage restoration layer positioned between the upper electrode and the lower electrode and being contracted and restored by a load,
A sensing unit for sensing a touch position and a touch load based on a change in mutual capacitance generated between the upper electrode and the lower electrode,
Wherein the tactile touch screen device comprises: The method of claim 1,
Wherein the upper electrode is formed in a pattern in which an open region generating fringe capacitance is symmetrical in the up, down, left, and right directions. 3. The method of claim 2,
Wherein the upper electrode is formed by connecting a plurality of unit patterns, and the open region is formed in an up, down, left, and right symmetry around the unit pattern. The method of claim 1,
Wherein the lower electrode is formed in a rectangular bar pattern. delete The method of claim 1,
The sensing unit
A tactile touch screen device that recognizes a signal having a value smaller than the initial mutual capacitance as a soft touch and recognizes a signal having a value larger than the initial mutual capacitance as a hard touch. The method of claim 1,
The shrinkage recovery layer
Shrinks or restores according to a load to change a distance between the upper electrode and the lower electrode. The method of claim 1,
A sealing structure provided on the outer periphery of the shrinkage restoration layer so as to prevent loss of the shrinkage restoration layer due to deformation and maintain the shrinkage restoration layer in a predetermined shape
Wherein the tactile touch screen device further comprises:

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