KR20090000921A - Touch screen - Google Patents

Abstract

A capacitive touch screen is provided to reduce manufacturing cost and high transparency by forming two axes, which forms coordinates, in a type of an independent array electrically discriminated with each other. A resistive first pattern bar(10) is arranged in a bar type on a transparent or non-transparent resistive substrate. A second pattern bar is arranged in parallel with the first pattern bar between the resistive arrays of the first pattern bar by having a higher resistance than the first pattern bar. The first pattern bar and the second pattern bar have various sizes and shapes.

Description

Touch screen {touch screen}

1 is a view showing the form of a single bar (Bar) of the pattern 1 of the touch screen according to the present invention.

2A and 2B illustrate various forms of a single bar of pattern 2 of a touch screen according to the present invention;

3A and 3B show a structure in which each of the bars of FIGS. 1 and 2A and 2B is arranged at the same time.

4A and 4B illustrate a wiring structure of pattern 1 of the present invention and a wiring structure of pattern 2;

5 is a block diagram showing an embodiment of a touch screen according to the present invention.

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

10: first pattern bar 20, 21: second pattern bar

30, 31: wiring 40: touch screen

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to touch screens having two-dimensional coordinates or anisotropic sensors, and more particularly to capacitive touch screens of a structure and type that take a method of proximity sensing.

In general, the touch screen has a two-dimensional coordinate system, and is a device for interpreting the position intended by the user. Among the touch sensors having two-dimensional coordinates, a touch screen, a touch pad, and a touch switch using a hand or a dedicated pen (Stylus) are used. It belongs to the category of, and is generally used on the liquid crystal display (LCD), plasma display panel (PDP), CRT (CRT) and the like.

Typically, these types of touch sensors are in the spotlight in personal portable devices, industrial control devices, POS terminals, unmanned guidance devices (KIOSK), remote controllers (Remote Controller), and the like. Convenience that can be used without a separate input device, the powerful and convenient interface of WYSIWYG (WYSIWYG) is widely used in almost all fields as a weapon, and it is a field that is expected to make a quantum leap.

More than thirty years after the first touch sensors were developed, they have now become an integral part of the electrical and electronics industry, but they are still used primarily on the surface of display devices mentioned above.

As a problem of the touch sensor mounted on the surface of such a display device, a decrease in visibility due to low optical transmittance, particularly in the case of a resistive touch screen using a polymer-based film, has a maximum transmittance level of about 90%. It has a light transmittance of about 80%. In addition, since the resistive film is operated only by physical contact, deterioration of the device and loss of function due to physical stress have been a problem.

In addition to the resistive touch screen, analog capacitive touch screens are mainly used for medium- and large-sized devices of 10 inches or more, especially when the device is installed once, such as an unmanned guide device (KIOSK), financial terminal (ATM), ticket machine / ticket machine, etc. Or is mainly used for embedded devices.

In addition, unlike the resistive film method, the position is calculated by direct proximity and contact from the human body, and since there is no film-like film on the surface, it has superior durability and high optical transmittance as compared to the resistive film method.

However, the analog capacitive touch screen is unstable due to unstable factors such as stray capacitance generated from peripheral devices, moisture content of the body when touched, or capacitive change that may occur due to ground state with the ground. Because it is sensitively affected, it is mainly used only in fixed and embedded devices, and there is a problem that cannot be used in mobile devices such as personal terminals.

Another type of touch sensor is an ultrasonic sensor, but the position is read using the vibration of the ultrasonic wave generated at the pole surface of the sensor, but an error is caused by factors such as dust and water, which are environmental elements absorbed by the ultrasonic wave. This also causes problems. In addition, when mounting on a display, it is troublesome to ensure normal operation only by following a difficult mounting rule according to ultrasonic characteristics.

In the case of the infrared sensor, as a typical side sensor, since the sensor operates on the top, bottom, left, and right sides of the side, the cause of the above problem is hardly affected, but it is a problem of manufacturing unit cost and the wavelength of the infrared region that may be included in visible light. It is rarely used in external devices because it is affected by

In the case of a touch pad mainly used for replacing a notebook or a mouse, since the structure is made of an opaque substrate that cannot be mounted on the surface of a display device, there is a problem of being limited to a function such as a mouse.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and belongs to the category of an electrostatic capacitive touch sensor, and two axes constituting the coordinates, X and Y, are bar-shaped or zigzag-shaped. Zigzag) has a form, and the object of the present invention is to provide a touch screen having a form of an independent arrangement electrically separated from each other.

In addition, the present invention has an independent structure compared to the existing touch sensor having a two-dimensional independent coordinate system of X and Y, and can be implemented simultaneously through a single layer while maintaining the two-dimensional independent coordinate system. Another object is to provide a touch screen that can be simplified manufacturing and can be competitive in terms of cost.

Touch screen according to the present invention for achieving the above object has the following configuration.

An electrically resistive first pattern bar arranged in a bar form on a transparent or opaque electrically resistive substrate, and having a higher electrical resistance than the first pattern bar again between the resistive arrays of the first pattern bar. Two pattern bars are arranged to have a structure parallel to each other with the first pattern bar. The first pattern bar and the second pattern bar may have various sizes and shapes.

The first pattern bar and the second pattern bar are electrically independent of each other, and each pattern has a constant resistance. For example, if there are 20 linear bars listed in the first pattern bar, they can be divided into bars 1 to 20, and bars 1 to 20 each have the same or similar level of electrical resistance error. Listed at even intervals. Similarly, the second pattern bar has a higher electrical resistance than the first pattern bar, and also has a bar or zigzag shape (this type may have various sizes and shapes). The bars are arranged at equal intervals with the same or similar level of electrical resistance error as the first pattern bar.

In particular, the first pattern bar having a lower electrical resistance than the second pattern bar has a form in which the end of the bar and the other end are connected with at least twice as much electrical resistance as the resistance of the bar itself. Have

Each of the first pattern bars and the second pattern bars listed above has wirings for transmitting and receiving signals, and are electrically connected to dedicated circuits for analyzing signals through the wirings.

In the present invention, since it is a device mainly for measuring the floating capacitance generated when contacting or approaching a finger or the like, in order to ensure a constant capacitance, the circuit may have physical resistance and electrical resistance from the outside. It has a protective film with transparent or opaque dielectric properties on its surface.

The protective film uses a dielectric material having dielectric properties, and the material may be made of a material having different dielectric properties depending on the electrical resistance according to the capacitance. The transparent substrate is mainly exemplified here using the dielectric properties of SiO 2, but any material having a suitable dielectric property may be used.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing the shape of a single bar (Bar) of the pattern 1 of the touch screen according to the present invention, the first pattern bar 10 has a structure of a pattern having a single straight bar shape, it has a zigzag shape . The bar here has a constant electrical conductivity.

In order to form such a bar shape, an opaque material such as gold paste, silver paste, or copper paste may be generally used, and other electrically conductive materials may be used for printing techniques such as screen printing, inkjet printing, pad printing, and transfer printing. Can be produced.

In the present invention, the transparent material for forming the bar may be mainly made of a well-known electrically conductive thin film coating such as indium tin oxide (ITO), antimony tin oxide (ATO), and the like. Through this, it is possible to produce a pattern of a certain shape as shown in FIG.

Selective etching can be mainly performed chemically and physically, and there are a variety of such methods. In the case of the bar of FIG. 1, the material having higher electrical conductivity is more suitable for measuring floating capacitance when an object such as a finger approaches or contacts, but in this case, it is most widely used among conductive thin films to manufacture a transparent sensor. The case where the ITO thin film coating layer is manufactured in the form of a bar as shown through a selective etching process will be described as an example.

The bar of FIG. 1 is in the form of a zigzag, which varies in accordance with the required electrical resistance and the size of the sensor. Here, the resistance (R) between the measuring points A (not shown) and B (not shown) is configured to about 20 to 60 Kilo Ohm.

2A and 2B illustrate various forms of a single bar of pattern 2 of a touch screen according to the present invention.

2A and 2B illustrate various structures having bars in the second pattern bars 20 and 21. Like bar 1, this bar is also electrically conductive. The method of constructing the pattern may be configured in the same manner as described with reference to FIG. 1, and the resistance between the measurement points A and B is always smaller than the resistance R of the first pattern bar 10 of FIG. 1. (R> R1)

3A and 3B illustrate structures in which bars of FIGS. 1 and 2A and 2B are arranged at the same time.

3A and 3B illustrate a form in which the first pattern bars 10 and the second pattern bars 20 and 21 are arranged at regular intervals. In particular, FIG. 3A illustrates a form in which the first pattern bar 10 and the second pattern bar 20 of FIG. 1 are arranged.

3B illustrates a form in which the first pattern bar 10 and the second pattern bar 21 are arranged. However, compared to the case of FIG. 3A, FIG. 3B has a relatively narrow spacing between the pattern and the pattern, and has a pattern in the form of a wing (flange) in which the shape of the second pattern bar 21 protrudes to the left and right sides.

This shape maximizes the contact area in order to maximize the floating capacity due to the contact or contact of the finger or the like.

Logically, the first pattern bar 10 and the second pattern bar 20, 21 may measure the position with only one pair when the surface of the sensor is touched with a finger or the like. This contact can improve accuracy when at least two pairs of arrays are in contact with the contact surface.

In the case of FIG. 3A, the contact area of the finger has a diameter of 4.5 to 8 mm, and when one pair of adjacent patterns 1 and 2 is viewed as a pair, two or more pairs of contacts may be used to more accurately measure a signal.

4A and 4B are diagrams showing the wiring structure of pattern 1 of the present invention and the wiring structure of pattern 2;

FIG. 4A shows the wiring 30 to which the second continuous pattern bar 20 is electrically connected. The structure of the wiring 30 is connected by a resistor (R) between each array so as to have an electrical resistance. The directions of the patterns 1 and 2 can be formed regardless of the width or length, but in this figure, the patterns 1 and 2 are arranged in the vertical direction.

In general, forming two-dimensional coordinates in a sensor has a structure in which the X-direction and the Y-direction cross each other, but the present invention describes a method that can be configured in a unidirectional direction consisting of X or Y only and the effects thereof. In this way, Fig. 4A logically has a signal on the X-axis. Here, Rx is a resistance of the wiring and has an arrangement of the pattern 2 and a constant electrical resistance.

The conductive Rx may be formed of carbon, silver, copper, I.T.O (Indium Tin Oxide) or a mixture thereof. Rr may be made of the same material as Rx as the transparent conductive pattern 2, and I.T.O is used in the present invention. Rx has a much higher electrical resistance than Rr. (Rr << Rx) The ratio of the electrical resistance of Rx and Rr is generally composed of 10: 1 or more. N represents the number of patterns 2, which can be configured differently according to the size of the sensor and the size of Rx.

4B illustrates the wiring 31 to which the continuous first pattern bar 10 is electrically connected. The wiring 31 connects the first pattern bars 10 to each other with an element having a small electrical resistance. Here, the wiring 31 mainly uses pastes, such as gold, silver, and copper, which are small in electrical resistance. FIG. 4B is a long line in the vertical direction similar to FIG. 4A, and the first pattern bar 10 has a signal in the Y direction.

5 is a configuration diagram showing an embodiment of a touch screen according to the present invention.

FIG. 5 is a diagram illustrating how the arrangement of the first pattern bar 10 and the second pattern bar 20 are configured at the same time. Here, the arrangement 1 and the arrangement 2 of the first pattern bar 10 and the second pattern bar 20 are configured to measure the X direction and the Y direction, respectively.

When an arbitrary object such as a finger or the like comes into contact with the sensor configured as shown in FIG. 5 to detect the coordinates, capacitance coupling is formed between the arbitrary object and each array.

Since the formed capacitance is detected slightly differently depending on the position, a signal is detected and converted into coordinate data by an external or integrated controller.

As described above, the present invention belongs to the category of an electrostatic capacitive touch sensor, and two axes constituting the coordinates, X and Y, have a bar shape or a zigzag shape, and are electrically connected to each other. It has the form of an independent array. Conventional capacitive touch sensors have a structure in which X and Y are connected to each other as resistance components, but in the present invention, the X and Y components are divided into separate components, respectively, to be combined with the existing resistance components. Simplify and manufacture the analysis algorithm by ensuring the clarity of the signal as a whole, because the signal itself occurs as a separate state of the X and Y signals, rather than through a complex analysis algorithm of the mixed signal generated in the structure This can bring about cost savings.

In addition, the present invention has an independent structure compared to the existing touch sensor having a two-dimensional independent coordinate system of X and Y. Conventional sensors with two-dimensional independent coordinate systems combine two or more independent layers to separate X and Y from each other. However, according to the present invention, since it can be implemented simultaneously through a single layer while maintaining a two-dimensional independent coordinate system, a more simplified manufacturing is possible, and this is economical, and thus can be competitive in terms of cost.

Although the above has been shown and described with respect to the preferred embodiments of the present invention, the present invention is not limited to the above-described embodiment, it is usually in the field of the present invention without departing from the gist of the invention claimed in the claims. Anyone of ordinary skill in the art can make various modifications, as well as such modifications are within the scope of the claims.

As described above, according to the touch screen according to the present invention, a new type of capacitance principle is applied, and a competitive manufacturing method and manufacturing cost reduction, high optical transmittance of at least 90% and up to 95%, and a hand or a pen are used. Has no deterioration, is a transparent material that can be mounted on the surface of the display, is resistant to water and contamination, and is not affected by infrared or light rays.

In addition, it is possible to configure a touch sensor that can be applied to non-fixed devices, such as personal terminals, mobile phones, and notebook displays, which have been pointed out as the limitations of the existing analog capacitance method.

In addition, the present invention can be applied to a variety of materials, such as a transparent substrate, an opaque substrate, a flexible circuit board, not the limited substrate mentioned above, and has a structure that can also secure the viability compared to the conventional two-dimensional coordinate sensing device It works.

Claims (6)

A plurality of first resistive first pattern bars arranged in a bar form on a transparent or opaque electrically resistive substrate; And a plurality of second pattern bars arranged between the resistive arrays of the plurality of first pattern bars, having a higher electrical resistance than the first pattern bars, and having a structure parallel to each other. screen. The method of claim 1, The first pattern bar and the second pattern bar are arranged on a single layer and are electrically independent of each other, and the plurality of first pattern bars and the second pattern bars each have the same or similar level of electrical resistance error and are uniform. Touch screen, characterized in that listed in the interval. The method of claim 1, The first pattern bar is a touch screen, characterized in that formed in a zigzag (Zigzag) or irregularities. The method of claim 1, The second pattern bar is a touch screen, characterized in that a plurality of flanges protruding to both sides of the bar body. The method of claim 1, Each of the first pattern bar and the second pattern bar has a respective wire for transmitting and receiving a signal. The method of claim 1, A touch screen comprising a protective film having a dielectric property transparent to its surface to ensure a constant capacitive property and to have a physical resistance and an electrical resistance from the outside.

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