KR20100025176A - Capacitive type structure of multi-touch input for acquiring location and intensity of force and making method thereof - Google Patents

Abstract

PURPOSE: A touch input structure for measuring contact position / pressing force according to multi touch of an electrostatic capacitive type and a manufacturing method thereof are provided to block interference between the pressing force by including a filler between an upper plate and a lower plate. CONSTITUTION: An upper electrode layer(112) is formed on one side of an upper plate(110). The upper plate is transformable through touch. A lower plate(120) is separated from the upper plate. A bottom electrode layer(122) facing to the upper electrode layer is formed on single-side of the lower plate. A bonding layer(130) is arranged on the circumference of the interval of the upper plate and the lower plate. The bonding layer connets the upper plate and the lower plate. A filler(140) is filled between the upper plate and the lower plate.

Description

Capacitive type structure of multi-touch input for acquiring location and intensity of force and making method according to capacitive multi-touch

The present invention relates to a touch input structure for measuring a touch position and a pressing force according to a capacitive multi-touch, and more particularly, having a filler between an upper and a lower electrode layer and interfering with a plurality of pressing forces applied during multi-touch. It relates to a touch input structure and a method of manufacturing the same that can obtain the exact position and strength of the pressing force by minimizing.

Recently, the touch input technology, which is in the spotlight, is used to select or input a function desired by a user, and is used in various electronic / communication devices such as a notebook, a personal digital assistant (PDA), a game machine, a mobile phone, and the like.

One example of the touch input technology used in mobile phones is Apple's iPhone. As the iPhone follows the capacitive method, as shown in FIG. 1, electrodes 12 and 13 are formed on the upper and lower surfaces of the glass substrate 10 to detect only the positions of the pressing points. The conventional touch input technology as shown in FIG. 1 provides a clean screen because it is not an obstacle in that light emitted from the liquid crystal panel is delivered to the user, and has an advantage of not harming the appearance of a mobile phone, but wearing gloves. In the case of input, there is a disadvantage that the input is not applied because the capacitance does not change. In addition, there is a limit to commercialization in a variety of devices, such as small electronic / communication devices as well as large electronic / communication devices are required because a small pressing force corresponding to about 150g when applying an input. In the conventional touch input technology, only the position of the multi-touch can be obtained, and there is a limitation in that the strength of the pressing force cannot be detected.

As a related art of touch input, there is a capacitive tactile sensor and a manufacturing method thereof (Korean Patent Publication No. 10-2008-0054187). As shown in FIG. 2, electrodes 56a and 56b are formed on the upper substrate 51 and the lower substrate 52, respectively, and a domed spacer 58 is provided around the electrode 56b. This tactile sensor acquires a change in capacitance to detect the position and intensity of the pressing force.

However, if a plurality of pressing forces are locally applied to the tactile sensor by multi-touch, the force is applied to the entire upper substrate 51 even though the pressing forces F ₁ and F ₂ are locally applied. Due to this, the upper substrate is deformed as shown in FIG. 3. Therefore, in the case of multi-touch, interference occurs between the pressing forces F ₁ and F ₂ applied locally at each point, and thus the position and intensity of each pressing force F ₁ and F ₂ cannot be accurately obtained. There was a limit. This interference phenomenon is more severe the shorter the distance between the plurality of pressing force (F ₁ , F ₂ ).

Thus, when locally applying a plurality of pressing forces F ₁ and F ₂ by multi-touch, development of a touch input technology capable of accurately detecting the strength and position of the pressing force at each point has been required.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to provide a capacitive multi-touch that can accurately obtain the strength and position of the pressing force by blocking the interference between the plurality of pressing forces. To provide a touch input structure and a manufacturing method for measuring the contact position and the pressing force according to.

Still another object of the present invention is to provide a touch input structure for measuring touch position and pressing force according to capacitive multi-touch, which can be variously applied to various electronic / communication devices using the touch input method as one module, and to manufacture the same. To provide a method.

An object of the present invention as described above, the upper electrode layer is formed on one surface, the upper plate deformable by touch:

A lower plate provided to be spaced apart from the upper plate by a predetermined interval, and having a lower electrode layer formed on a surface of the upper surface facing the upper electrode layer;

An adhesive layer provided around the upper plate and the lower plate to connect the upper plate and the lower plate; And

It can be achieved by a capacitive touch input structure for a multi-touch including a filler filled between the upper plate and the lower plate.

In addition, the filler uses an elastic material.

At this time, the elastic material may be composed of a transparent polymer film, a transparent liquid, a transparent sol or a transparent gel.

In this case, the transparent gel may use silicone or polydimethylsiloxane.

In addition, the upper plate and the lower plate is preferably composed of a transparent material.

In this case, the upper and lower plates may be used glass or polymer film.

And, the adhesive layer is preferably provided around the edge of the upper plate and the lower plate.

In addition, the adhesive layer may use a UV curing agent.

The lower electrode layer may include a plurality of lower electrodes, and a spacer may be further included between the plurality of lower electrodes.

At this time, the spacer preferably has elasticity.

The upper electrode layer and the lower electrode layer are strip-shaped electrodes, and a plurality of electrodes formed on the upper electrode layer and the lower electrode layer cross each other.

In addition, the upper electrode layer and the lower electrode layer may be composed of indium tin oxide (ITO) or carbon nanotubes (CNT).

And, the gap between the upper plate and the lower plate can be configured to 0.1 ~ 100㎛.

Moreover, it is preferable that the thickness of an upper board becomes 100-1500 micrometers.

In addition, the side of the touch input structure is completely fixed, and can be configured such that there is no displacement change and tilt change of the side.

Alternatively, the side of the touch input structure is simply supported and can be configured such that there is no change in displacement of the side.

An object of the present invention as described above is another step, forming an electrode layer on one surface of at least two transparent substrates;

Providing a substrate such that electrode layers formed on the substrate cross each other; And

A method of manufacturing a touch input structure for measuring a contact position and a pressing force according to a capacitive multi-touch, including the step of adhering a substrate including a filler in an internal space formed between the substrates.

The method may further include forming spacers between the electrode layers formed on any one of the substrates, between the electrode layer forming step and the substrate providing step.

And, when the filler is a gel, gel or liquid phase, the step of bonding including the filler, forming an adhesive layer around the edge of the upper plate and the lower plate leaving an injection hole for injecting the filler; Injecting a filler through an injection hole; And filling the injection hole.

In addition, when the filler is in a solid phase, the bonding including the filler may include placing the filler between the internal regions of the substrate; And bonding the edges of the upper plate and the lower plate using an adhesive layer.

Therefore, according to the exemplary embodiment as described above, a filling material is provided between the upper plate and the lower plate, so that even if a plurality of pressing forces are applied, the pressing force is accurately obtained by blocking the interference between the pressing forces.

In addition, since the strength and position of the pressing force can be obtained together, there is an advantage of providing various applications to the user based on the strength and position of the pressing force.

In addition, since the production is simple and can be manufactured as a module, any electronic / communication device employing a touch input method can be utilized regardless of its type.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention. Prior to describing the present invention, if it is determined that a detailed description of related known functions and configurations may unnecessarily obscure the subject matter of the present invention, the description thereof will be omitted.

<Configuration of Touch Input Structure>

4 is a perspective view of a touch input structure for measuring a contact position and a pressing force according to the capacitive multi-touch according to the present invention, and FIG. 5 is a side cross-sectional view taken along the line A-A of FIG. 4. According to the present invention, the touch input structure for measuring the touch position and the pressing force according to the capacitive multi-touch includes: an upper plate 110 on which the upper electrode layer 112 is formed, and a lower plate 120 on which the lower electrode layer 122 is formed. , Filler 140 and spacer 150 are included.

The upper plate 110 is a member that is elastically deformed when a pressing force is applied, and the touch input structure for multi-touch according to the present invention is provided with a liquid crystal panel 200 at a lower side thereof, which is applicable to a touch screen, and the upper plate 110. It is preferable to comprise a transparent material. An example of a transparent material is glass or a polymer film (eg, a polyester film, a polyimide film), etc. When glass is used as the top plate 110, it has excellent durability and requires about 70 g of pressing force. There is a characteristic that. On the other hand, the polymer film is sufficient to induce a change in capacitance even by applying a small pressing force (in about 30g), but has a property of inferior durability compared to glass. Accordingly, in consideration of such material properties, the top plate 110 is selected to be suitable for the environment of an electronic / communication device in which a touch input structure for contact position and pressing force measurement according to the capacitive multi-touch according to the present invention is used.

And, the thickness of the upper plate 110 is preferably configured to be about 100 ~ 1500㎛. When the thickness of the upper plate 110 is less than 100 μm, there may be a problem in durability to endure the pressing force, and when the thickness of the upper plate 110 exceeds 1500 μm, the change in capacitance due to the pressing force is small, and the measurement sensitivity may be lowered.

The lower plate 120 is a member provided to be spaced apart from the upper plate 110 by a predetermined interval, and is preferably made of a transparent material like the upper plate 110. The spaced interval between the upper plate 110 and the lower plate 120 is less than 100㎛, it is configured to be about 0.1 ~ 100㎛. If the distance between the upper plate 110 and the lower plate 120 is less than 0.1㎛, it is difficult to accommodate the deformation of the upper plate 110 when the pressing force is applied, if it exceeds 100㎛ it may be a barrier to miniaturization and the change of capacitance Measurement sensitivity may be somewhat lowered.

The upper electrode layer 112 and the lower electrode layer 122 are formed on one surface of the upper plate 110 and the lower plate 120, respectively. The upper electrode layer 112 formed on one surface of the upper plate 110 and the lower electrode layer 122 formed on one surface of the lower plate 120 are strip-shaped electrodes, and are provided in plural as shown in FIG. 4. In addition, the upper electrode layer 112 and the lower electrode layer 122 are provided in directions crossing each other in a direction facing each other. In the capacitive multi-touch touch input structure according to the present invention, the liquid crystal panel 200 may be preferably added, and the upper electrode layer 112 and the lower electrode layer 122 are composed of transparent electrodes. An example of a transparent electrode is indium tin oxide (ITO) or carbon nanotube (CNT).

The adhesive layer 130 is a member that connects the upper plate 110 and the lower plate 120, and is preferably provided around the edges of the upper plate 110 and the lower plate 120. The adhesive layer 130 simultaneously serves as a support layer, and may be an ultraviolet curable adhesive (UV adhesive) as an example of the adhesive layer 130. The upper plate 110 and the lower plate 120 are spaced apart by a predetermined interval due to the adhesive layer 130, the thickness of the adhesive layer 130 is 0.1 ~ 100㎛.

The filler 140 is provided between the upper plate 110 and the lower plate 120. Filler 140 uses an elastic material. In addition, the filler 140 is preferably used that is transparent and does not change color. The filler 140, which is an elastic material, serves to block the interference between the pressing forces when a plurality of pressing forces are applied to the upper plate 110. Hereinafter, the role of the filler 140 will be described in detail.

In the case where the filler 140 is not provided, as shown in FIG. 6A, even when a plurality of pressing forces are applied, the top plate 110 is deformed at each point due to the durability of the top plate 110. There is a strong tendency to deform. That is, although the pressing force (F ₁ , F ₂ ) is applied at two points, the deformation of the top plate 110 by the pressing force occurs to the maximum between the two points to which the pressing force is applied. Therefore, it is difficult to accurately obtain the position and intensity of the pressing force at the point where a plurality of pressing forces F ₁ and F ₂ are applied, and this phenomenon is more pronounced as the distance between the two points to which the pressing force is applied is closer. (Force interference). That is, the resolution decreases in obtaining the pressing force.

On the other hand, when the filler 140 is provided, as shown in Figure 6b, when a plurality of pressing force (F ₁ , F ₂ ) is applied, the deformation of the top plate 110 is noticeably at that point. This is due to the elasticity of the filler 140, the filler 140 located at the lower portion of the pressing force applied point is pushed to the periphery by the pressure of the pressing force (F ₁ , F ₂ ), the filler pushed out to the periphery The upper plate 110 around the point where the pressing force F ₁ , F ₂ is applied by the 140 is relatively deformed to the upper side. In other words, the deformation of the upper plate 110 at the point where the pressing force (F ₁ , F ₂ ) is applied is to react more effectively than when the filler 140 is not provided. Therefore, when the pressing force (F ₁ , F ₂ ) is applied at two points, unlike the case of Figure 6a where the deformation of the upper plate 110 is prominent between the two points, the interference between the pressing force is blocked.

An example of such a filler 140 may be a transparent polymer film, a transparent liquid, a transparent sol, or a transparent gel. One example of the transparent gel used as the filler 140 is silicone, polydimethylsiloxane (PDMS: polydimethylsiloane). In order to minimize the influence of the environment in which the touch input structure is placed in obtaining the strength and position of the pressing force, the filler 140 uses a material that is not thermally expanded or a non-conductive material (eg, a non-conductive oil, etc.). This is preferred.

The spacer 150 is provided between the plurality of lower electrodes 122. Spacer 150 is also a member that serves to block the interference between the pressing force when a plurality of pressing force is applied, it is preferable to use an elastic material. The spacer 150 may be used regardless of its kind as long as it is a material having elasticity such as the filler 140. In addition, the shape of the spacer 140 may be variously configured in a dome shape, a hexahedron shape, and the like, and is not limited to the shape.

The side of the touch input structure for contact position and pressing force measurement according to the capacitive multi-touch according to the present invention having the structure as described above may be configured in a completely fixed state or a simple supporting state. The fully fixed state represents a state where there is no change of the displacement and the slope of the side, and the simple support state represents a state where there is no change of the side of the displacement.

<Production method>

Hereinafter, with reference to the accompanying drawings will be described a manufacturing method of the touch input structure for measuring the contact position and the pressing force according to the capacitive multi-touch according to the present invention. 7 is a flowchart illustrating a method of manufacturing a multi-touch touch input structure according to the present invention.

First, an electrode layer is formed on one surface of at least two substrates (S100). At this time, it is preferable that the substrate used is a transparent material. An example of a method of forming an electrode layer is a thermochemical vapor deposition method. A plurality of electrode layers are formed in a strip shape, and the plurality of electrode layers are provided in parallel directions. The electrode layer may be formed using indium tin oxide or carbon nanotubes.

One of the transparent substrates on which the electrode layer is formed in this manner is used as the upper plate 110, and the other is used as the lower plate 120. Hereinafter, the electrode layer formed on the upper plate is referred to as the upper electrode layer 112, and the electrode layer formed on the lower plate 120 is referred to as the lower electrode layer 122.

After forming the electrode layer, the spacer 150 may be formed between the plurality of electrode layers formed on any one of the two substrates (S150). It is preferable to use the spacer 150 having an elastic property, and the substrate on which the spacer 150 is formed may be used as the lower plate 120 as shown in FIG. 5.

Next, it is positioned to bond the two substrates on which the electrode layers are formed. At this time, the substrate is positioned so that the electrode layer formed on each substrate to cross (S200).

Next, the electrode layers formed on the upper plate 110 and the lower plate 120 are bonded to face each other. At this time, a filler is provided between the upper plate and the lower plate (S2300). The upper plate 110 and the lower plate 120 are bonded so that the upper electrode layer 112 and the lower electrode layer 122 cross each other. UV curing agent may be used as an example of the adhesive layer 130. The filler 140 is an elastic material, and may be a solid phase such as a polymer film, a liquid phase such as a two-component silicone, a gel or a sol, and will be described for each case.

When the filler 140 is in a solid phase, the filler 140 is positioned in an inner region between the upper plate 110 and the lower plate 120 in the upper plate 110 and the lower plate 120 (S310). At this time, the size of the filler 140 is configured to be somewhat smaller than the size of the upper plate 110 and lower plate 120, it is preferable to ensure a space for forming the adhesive layer 130. Next, the adhesive layer 130 is formed on the edges of the upper plate 110 and the lower plate 120 in the state where the filler 140 is provided to bond the upper plate 110 and the lower plate 120 (S320). In this case, the thickness of the filler 140 and the thickness of the adhesive layer 130 are formed to be the same so that there are no voids in the region where the filler 140 is provided, that is, the inner region formed by the adhesion of the upper plate 110 and the lower plate 120. .

When the filler 140 is a gel, a sol, or a liquid phase, the upper plate 110 and the lower plate 120 are first adhered using the adhesive layer 130. However, at this time, leaving the injection hole for injecting the filler 140 is bonded (S310 '). The adhesive layer 130 is formed around the edges of the upper plate 110 and the lower plate 120 to form a space therein. Then, the filler 140 is injected through the injection hole (S320 ′). Filled filler 140 is filled in the inner space without gap. When there is a gap in the internal space between the upper plate 110 and the lower plate 120 filled with the filler 140, it is difficult to block the interference between the plurality of pressing forces, so that the resolution is reduced to obtain the position and strength of the pressing force. After the injection of the filler 140 is finished, the injection hole is filled again using the adhesive layer 130 (S330 '). Even in this case, it is preferable that the gap is not formed in the inner region formed by the adhesion of the upper plate 110 and the lower plate 120.

< Pressing  How to measure strength and position>

8 is an example of a multi-touch touch input structure according to the present invention. A circuit diagram for detecting the strength and position of the pressing force by outputting signals from the upper electrode layer 112 and the lower electrode layer 122 formed to face each other in a matrix form is shown. to be.

Input terminals and output terminals are connected to the electrode layers 112 and 122, respectively. A sinusoidal voltage Vi is applied to the input terminal 301, and the output of the output terminal 302 is connected to the negative input terminal of the analog amplifier 400. The positive input terminal of the analog amplifier 400 is grounded, and the output terminal includes a peak detector 500 for detecting an amplitude peak value of the output voltage.

The output value Vout at the output terminal of the analog amplifier 400 is expressed by Equation 1 below.

(Cpix: capacitance to be measured, Cr: feedback capacitance of analog amplifier)

According to this relationship, when the sine wave Vi is applied to the input terminal, the amplitude changed according to the capacitance change between each of the upper electrode layer 112 and the lower electrode layer 122 is a predetermined level by the analog amplifier 400 of the output terminal. Is amplified. The amplified signal is detected through the peak detector 500, and the position and intensity of the pressing force can be detected by detecting the change in capacitance from the amplitude peak value.

< Variant >

9 is a perspective view illustrating a state in which a liquid crystal panel 200 is provided below a touch input structure for measuring a contact position and a pressing force according to a capacitive multi-touch according to the present invention. The liquid crystal panel may be an organic light emitting diode (OLED), an electroluminescent display (ELD), a liquid crystal display (LCD), a plasma display panel (PDP), or the like.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, it is possible to make various modifications or variations without departing from the spirit and scope of the invention. Accordingly, the appended claims will cover such modifications and variations as long as they fall within the spirit of the invention.

The following drawings, which are attached in this specification, illustrate the preferred embodiments of the present specification, and together with the detailed description of the present invention, serve to further understand the technical spirit of the present invention. It should not be interpreted.

1 is a side cross-sectional view as a first embodiment of a touch input structure for implementing a conventional multi-touch;

2 is a side cross-sectional view as a second embodiment of a touch input structure for implementing a conventional multi-touch;

3 is a deformed state diagram of an upper substrate when a pressing force is applied to two points of the touch input structure of FIG.

4 is a perspective view of a touch input structure for measuring a contact position and a pressing force according to a capacitive multi-touch according to the present invention;

FIG. 5 is a side cross-sectional view of a touch input structure for measuring a contact position and a pressing force according to the capacitive multi-touch of FIG. 4;

Figure 6a is a case where the filler is not provided, the deformation state of the upper plate when the pressing force is applied to the two points by multi-touch,

Figure 6b is a case where the filler is provided, the deformation state of the upper plate when the pressing force is applied to two points with multi-touch,

7 is a flowchart illustrating a method of manufacturing a touch input structure for measuring a contact position and a pressing force according to a capacitive multi-touch according to the present invention;

8 is a configuration diagram of an equivalent circuit for detecting a pressing force from a touch input structure for measuring a contact position and a pressing force according to a capacitive multi-touch according to the present invention;

9 illustrates a state in which a liquid crystal panel is provided under a touch input structure for measuring a contact position and a pressing force according to a capacitive multi-touch according to the present invention.

<Description of the symbols for the main parts of the drawings>

10: glass substrate

12,13: electrode

51: upper substrate

52: lower substrate

54; glue

56a: upper electrode

56b: lower electrode

57: insulation layer

58, 150: spacer

110: tops

112: upper electrode layer

120: bottom plate

122: lower electrode layer

130: adhesive layer

140: filling material

200: liquid crystal panel

301: input terminal

302: output terminal

400: analog amplifier

500: peak detector

Claims (20)

The upper electrode layer is formed on one surface, the upper plate deformable by touch: A lower plate provided to be spaced apart from the upper plate by a predetermined interval, and having a lower electrode layer formed on a surface of the upper surface opposite to the upper electrode layer; An adhesive layer provided around the upper plate and the lower plate to connect the upper plate and the lower plate; And A touch input structure for measuring a contact position and a pressing force according to the capacitive multi-touch, characterized in that it comprises a filler filled between the upper plate and the lower plate. The method of claim 1, The filler is a touch input structure for measuring the contact position and pressing force according to the capacitive multi-touch, characterized in that the elastic material. The method of claim 2, The elastic material is a touch input structure for measuring the contact position and pressing force according to the capacitive multi-touch, characterized in that the transparent polymer film, transparent liquid, transparent sol or transparent gel. The method of claim 3, wherein The transparent gel is polydimethylsiloxane or silicon, the touch input structure for measuring the contact position and pressing force according to the capacitive multi-touch. The method of claim 1, The upper plate and the lower plate is a touch input structure for measuring the contact position and pressing force according to the capacitive multi-touch, characterized in that the transparent. The method of claim 5, wherein The upper plate and the lower plate is a touch input structure for measuring the contact position and pressing force according to the capacitive multi-touch, characterized in that the glass or polymer film. The method of claim 1, The adhesive layer is a touch input structure for measuring the contact position and the pressing force according to the capacitive multi-touch, characterized in that provided around the edge of the upper plate and the lower plate. The method of claim 7, wherein The adhesive layer is a touch input structure for measuring the contact position and pressing force according to the capacitive multi-touch, characterized in that the UV curing agent. The method of claim 1, The lower electrode layer is composed of a plurality of lower electrodes, the touch input structure for measuring the contact position and the pressing force according to the capacitive multi-touch, characterized in that further comprising a spacer between the plurality of lower electrodes. The method of claim 9, The spacer is a touch input structure for measuring the contact position and pressing force according to the capacitive multi-touch characterized in that it has an elasticity. The method of claim 1, The upper electrode layer and the lower electrode layer is a strip-shaped electrode, A touch input structure for measuring a touch position and a pressing force according to a capacitive multi-touch, characterized in that a plurality of electrodes formed on the upper electrode layer and the lower electrode layer intersect each other. The method of claim 1, And the upper electrode layer and the lower electrode layer are indium tin oxide (ITO) or carbon nanotubes (CNT). The method of claim 1, The contact between the upper plate and the lower plate is 0.1 ~ 100㎛ Touch input structure for measuring the position and pressing force according to the capacitive multi-touch. The method of claim 1, The thickness of the upper plate is a touch input structure for measuring the contact position and pressing force according to the capacitive multi-touch, characterized in that the 100 ~ 1500㎛. The method of claim 1, The side of the touch input structure is a completely fixed state, the touch input structure for measuring the contact position and pressing force according to the capacitive multi-touch, characterized in that there is no displacement change and tilt change of the side. The method of claim 1, Side of the touch input structure is a simple supported state, the touch input structure for measuring the touch position and pressing force according to the capacitive multi-touch, characterized in that there is no displacement change of the side. Forming an electrode layer on one surface of at least two transparent substrates; Providing the substrate such that the electrode layers formed on the substrate cross each other; And A method of manufacturing a touch input structure for measuring a contact position and a pressing force according to a capacitive type multi-touch, comprising the steps of: adhering the substrate to a space formed between the substrates. The method of claim 17, Between the electrode layer forming step and the substrate providing step, And forming a spacer between the plurality of electrode layers formed on any one of the substrates, wherein the touch input structure for measuring the touch position and the pressing force according to the capacitive multi-touch. The method of claim 17, The filler is in sol, gel or liquid form, and Bonding including the filler, Forming an adhesive layer around edges of the upper plate and the lower plate, leaving an injection hole for injecting the filler; Injecting a filler through the injection hole; And Filling the injection hole; Method of manufacturing a touch input structure for measuring the contact position and pressing force according to the capacitive multi-touch characterized in that it comprises a. The method of claim 17, The filler is in solid phase, and Bonding including the filler, Positioning the filler between inner regions of the substrate; And Bonding the edges of the upper plate and the lower plate using the adhesive layer; and a touch input structure for measuring touch position and pressing force according to a capacitive multi-touch.

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