KR20100043680A

KR20100043680A - Touch panel

Info

Publication number: KR20100043680A
Application number: KR1020080102802A
Authority: KR
Inventors: 김태훈
Original assignee: 엘지디스플레이 주식회사
Priority date: 2008-10-20
Filing date: 2008-10-20
Publication date: 2010-04-29

Abstract

PURPOSE: A touch panel is provided to prevent the short-circuit between a conductive adhesive and metallic wires through the press of an upper substrate and a lower substrate. CONSTITUTION: The first and second transparent electrodes are formed in the first and second substrates respectively. The first and second metallic electrodes(16a,16b) are formed at the edges of the first and second transparent electrodes. The first and second signal lines are formed on the first substrate and apply a voltage signal to the first and second metallic electrodes. An FPC(Flexible Printed Circuit) is formed in the first substrate and connects an external power source to the first and second signal lines. A contact line(14) connects the first metallic electrode to the first signal line.

Description

Touch panel {Touch panel}

The present invention relates to a touch panel, and more particularly, to a touch panel that can prevent a short defect.

In order to efficiently use various electronic devices, a touch panel for inputting a signal on a display surface of a display device without a remote controller or a separate input device is widely used. That is, the display surface of an electronic notebook, a flat panel display device such as a liquid crystal display device (LCD), a plasma display panel (PDP), an electro luminescence (EL), and an image display device such as a cathode ray tube (CRT). Is used to allow the user to select the desired information while viewing the image display device.

Such a touch panel may be classified into a resistive type, a capacitive type, an infrared sensor type, or an optical sensor type according to a method of sensing a touch.

The touch panel has a structure in which an upper transparent substrate on which an upper electrode is formed and a lower transparent substrate on which a lower electrode is formed are stacked with a predetermined space.

Therefore, when a certain point of contact such as a pen or a finger is brought into contact with the upper substrate on which the upper electrode is formed, the upper electrode formed on the upper substrate and the lower electrode formed on the lower substrate are energized with each other, and the resistance of the position After reading the voltage value changed by the value or the capacitor value, the device finds the position coordinate according to the change of the potential difference.

Since the conventional touch panel is provided on the display surface of the liquid crystal display device and used as a signal input means as described above, the display panel covers a viewing area corresponding to the display surface of the display device and the display area. So that it is divided into a dead space area formed around the display area. In addition, the upper and lower substrates are bonded by the insulating adhesive in the dead space.

As illustrated in FIG. 1, transparent electrodes 3 and 4 are respectively formed on inner surfaces of rectangular PET substrates 1 and 2 having a rectangular shape corresponding to the display surface of the display device. Are bonded in the dead space region by an insulating adhesive at regular intervals.

The first metal electrode 5 is formed in the upper and lower dead space regions on the upper substrate, and the second metal electrode 6 is formed in the left and right dead space regions on the lower substrate.

Therefore, when a point of contact with the point of the upper substrate 1 with a pen or a finger, the transparent electrodes (3, 4) are in contact with each other at the point to output a voltage value changed by the resistance value of the position.

Since the voltage value changed by the resistance value or the capacitor value of the contacted position is to be read as described above, a signal line for applying a voltage to the transparent electrode and reading the voltage value changed according to any contacted position should be connected.

Such signal lines are directly connected to external voltage sources Vcc and Vss through FPC (Flexible Printed Cable) (not shown) formed on one side of the lower substrate to apply voltage signals from the outside, respectively. It is connected to each of the second metal electrodes.

Meanwhile, although the second metal electrode 6 is directly connected to the signal line formed on the lower substrate, the first metal electrode 5 formed on the upper substrate is connected to the signal line through the contact wiring 8 formed on the lower substrate.

In this case, the first metal electrode 5 formed on the upper substrate and the contact wiring 8 formed on the lower substrate are contacted through the doped conductive adhesive 9.

However, when the conductive adhesive 9 dotting is formed on the wiring as described above, the conductive adhesive 9 is led to the outer portion of the first metal wiring 5 by the pressing of the upper substrate and the lower substrate to adjoin. There is a problem that can cause metal wiring and short defects.

An object of the present invention for solving the above problems is to provide a touch panel that can prevent a short defect.

According to an exemplary embodiment of the present invention, a touch panel includes a first substrate and a second substrate, first and second transparent electrodes formed on inner surfaces of the first and second substrates, and the first and second substrates. A plurality of first and second metal electrodes formed on each edge of the transparent electrode, a voltage signal applied to each of the first and second metal electrodes, and a plurality of first and second signal lines formed on the first substrate, An FPC formed on one side of the first substrate so that a voltage signal from the outside is applied to the first and second signal lines, and connecting an external voltage source and the first and second signal lines, and a first formed on the first substrate. A contact wiring formed on the second substrate at a position corresponding to the first metal electrode to connect the metal electrode and the first signal line formed on the second substrate, wherein the contact wiring and the first metal electrode are formed in the hole. Through the conductive adhesive formed It is contacted.

The hole is formed in the contact wiring or the first metal electrode and is formed to have a width corresponding to 2/3 of the width of the contact wiring or the first metal electrode.

The conductive adhesive formed in the hole is dotting by a dispenser.

Each of the first signal line and the contact wiring formed on the second substrate is formed with the second transparent electrode and the insulating layer interposed therebetween.

The touch panel according to the present invention forms a conductive adhesive inside the hole, thereby preventing the conductive adhesive from being drawn out to the outer portion of the metal wiring or the contact wiring by the pressing of the upper substrate and the lower substrate, thereby causing a short defect with the adjacent metal wiring. It can work.

In addition, the touch panel according to the present invention has an effect of reducing the width of the metal wiring or contact wiring to which the conductive adhesive is doped by forming the conductive adhesive inside the hole.

Hereinafter, a touch panel according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a schematic plan view of a touch panel according to the present invention, FIGS. 3A and 3B are plan views illustrating metal electrodes, signal lines, and contact wirings of the upper and lower substrates of FIG. 2, and FIG. 4A is the I-I of FIG. 2. 4 is a cross sectional view taken along the line II-II in FIG. 2.

As shown in FIG. 2, the touch panel 100 includes a viewing area corresponding to a display surface of a display device and a dead space 200 formed around a display area to surround the display area. Area). In addition, the upper and lower substrates are bonded by the insulating adhesive in the dead space 200.

3A shows an upper substrate of the touch panel 100, and FIG. 3B shows a lower substrate of the touch panel 100, and II-II 'of FIG. 4A and FIG. Referring to Figure 4b is a cross-sectional view in more detail as follows.

As shown in FIGS. 3A, 3B, 4A, and 4B, the first and second transparent electrodes 12a are respectively formed on the inner surfaces of the flexible and transparent upper and lower substrates 10a and 10b, such as poly ethylene terephtalate (PET). 12b) are formed, and the upper and lower substrates are bonded at a dead space region by an insulating adhesive at regular intervals.

The first metal electrode 16a is formed in the upper and lower dead space regions of the upper substrate, and the second metal electrode 16b is formed in the left and right dead space regions of the lower substrate.

In addition, a second signal line connected to an external voltage source (Vcc, Vss) through the FPC (Flexible Printed Cable) 300 formed on one side of the lower substrate to apply a voltage signal from the outside to the second metal electrode 16b on the lower substrate. 18b is provided.

At this time, since the second metal electrode 16b is electrically connected to the second transparent electrode 12b, the second metal electrode 16b is formed on the second transparent electrode 12b, but the second signal line 18b is connected to the second metal electrode 16b. The insulating layer 32 is formed between the second transparent electrode 12b and the second signal line 18b so as to be electrically connected but not electrically connected to the second transparent electrode 12b. The contact wiring 14 is also insulated from the second transparent electrode 12b with the insulating film 32 interposed therebetween.

In order to apply a voltage signal from the outside to the first metal electrode 16a formed on the upper substrate, a contact wiring 14 is formed on the lower substrate so as to correspond to the first metal electrode 16a. 14 is connected to the first signal line 18a connected to external voltage sources Vcc and Vss through an FPC (Flexible Printed Cable) 300 formed at one side of the lower substrate.

In addition, the first metal electrode 16a formed on the upper substrate and the contact wiring 14 formed on the lower substrate are contacted through a doped conductive adhesive 20. The conductive adhesive 20 is formed by contact wiring ( It is formed by dotting (dotting) inside the hole 22 formed in the 14).

The hole 22 is formed in the process of forming the contact wiring 14. That is, after depositing a metal film for contact wiring, patterning is performed to simultaneously form contact wiring and holes.

At this time, since the conductive adhesive is doped by a dispenser, the hole 22 is preferably formed in a circular shape, and preferably formed in a width corresponding to 2/3 of the width of the contact wiring 14 or the metal wiring 16a. Do. For example, if the width of the electrode is 1.5 mm, the width of the hole 22 is preferably about 1.0 mm.

Therefore, as in the present invention, by forming the conductive adhesive 20 in the hole 22, the conductive adhesive 20 is led to the outer portion of the metal wiring or the contact wiring by the pressing of the upper substrate and the lower substrate, the adjacent metal wiring It is possible to prevent the cause of the field and the short failure.

In addition, by forming the conductive adhesive 20 in the hole 22 as in the present invention, it is possible to reduce the width of the metal wiring or contact wiring to which the conductive adhesive 20 is doped.

In addition, as in the present invention, by forming the conductive adhesive 20 in the hole 22, the outer withdrawal of the conductive adhesive is reduced, so that the spreading range for the adhesive extraction amount is widened.

4B, the hole 22 is formed in the contact wiring 14, but as shown in FIG. 5, the hole 22 may be formed in the first metal electrode 16a.

Claims

A first substrate and a second substrate;

First and second transparent electrodes formed on inner surfaces of the first and second substrates, respectively;

A plurality of first and second metal electrodes formed on edges of the first and second transparent electrodes, respectively;

Applying a voltage signal to each of the first and second metal electrodes, and a plurality of first and second signal lines formed on the first substrate;

An FPC that is formed on one side of the first substrate so that a voltage signal from an outside is applied to the first and second signal lines, and connects an external voltage source and the first and second signal lines;

A contact wiring formed on a second substrate at a position corresponding to the first metal electrode to connect the first metal electrode formed on the first substrate and the first signal line formed on the second substrate;

And the contact wiring and the first metal electrode are in contact with each other through a conductive adhesive formed in the hole.

The method of claim 1, wherein the hole

The touch panel is formed on the contact wiring or the first metal electrode.

The method of claim 1, wherein the hole

And a width corresponding to 2/3 of a width of the contact wiring or the first metal electrode.

The method of claim 1, wherein the first signal line formed on the second substrate is

And a second transparent electrode and an insulating layer interposed therebetween.

The method of claim 1, wherein the contact wiring is