Touch panel and manufacturing method thereof

A touch panel and a manufacturing method thereof are provided. The touch panel has a touch region and a trace region and includes a substrate, a touch device, a shielding trace, and a plurality of conductive traces. The touch device is disposed on the substrate in the touch region and includes a plurality of electrode pads. The shielding trace and the conductive traces are disposed on the substrate in the trace region. At least a part of the conductive traces is electrically connected to the touch device. The shielding trace includes a first trace layer and a second trace layer electrically connected to each other. The shielding trace is disposed between two of the conductive traces, the first trace layer at least partially overlaps the second trace layer, and the shielding trace doesn't overlap the conductive traces.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a touch panel and a manufacturing method thereof, more particularly to a touch panel with a shielding trace for reducing signal interference.

2. Description of the Prior Art

Since the touch panel provides the user with the human-machine interaction experience when using the display device, it has gradually become an input device for various electronic products, such as smart phones, tablet computers, and smart refrigerators. In a common capacitive touch panel, multiple sensing electrodes are provided to sense the touching of the user, and the sensing electrodes are made of indium tin oxide (ITO) to prevent the images watched by the user from being affected. Since the resistance of ITO is higher than that of metal, non-transparent metal traces are used for connecting the sensing electrodes to pads used as an external output/input terminal in the conventional touch panel. However, with the development of touch technology, the region for disposing the non-transparent metal traces is gradually narrowed, so that capacitive coupling between the metal traces for transmitting the driving signals and the metal traces for transmitting the receiving signals is increased, resulting in the signal interference between them which reduces touch accuracy.

SUMMARY OF THE INVENTION

An embodiment of the present invention provides a touch panel having a touch region and a trace region disposed at least on one side of the touch region. The touch panel includes a substrate, a touch device, a first shielding trace and a plurality of conductive traces. The touch device is disposed on a top surface of the substrate in the touch region, and the touch device includes a plurality of electrode pads. The first shielding trace is disposed on the top surface of the substrate in the trace region and insulated from the touch device. The first shielding trace includes a first trace layer and a second trace layer electrically connected to each other, and in a direction perpendicular to the top surface of the substrate, the first trace layer at least partially overlaps the second trace layer. The conductive traces are disposed on the top surface of the substrate in the trace region, and at least a part of the conductive traces is electrically connected to the touch device. The first shielding trace is disposed between two of the conductive traces, and in the direction, the first shielding trace doesn't overlap the conductive traces.

Another embodiment of the present invention provides a touch panel having a touch region and a trace region disposed at least on one side of the touch region. The touch panel includes a substrate, a touch device and a first shielding trace. The touch device is disposed on a top surface of the substrate in the touch region, and the touch device includes a plurality of electrode pads. The first shielding trace is disposed on the top surface of the substrate in the trace region and insulated from the touch device, and at least a part of the conductive traces is electrically connected to the touch device. The first shielding trace includes a first trace layer and a second trace layer electrically connected to each other, in a direction perpendicular to the top surface of the substrate, the first trace layer at least partially overlaps the second trace layer, and the second trace layer and the electrode pads are formed of a same transparent conductive pattern layer or a same metal mesh layer.

Another embodiment of the present invention provides a manufacturing method of a touch panel. Firstly, a substrate is provided. Then, a touch device is formed on the substrate in a touch region, and a shielding trace and a plurality of conductive traces are formed on the substrate in a trace region. The shielding trace is disposed between two of the conductive traces. The touch device is insulated from the shielding trace and includes a plurality of electrode pads, and the shielding trace includes a first trace layer and a second trace layer electrically connected to each other. In a direction perpendicular to a top surface of the substrate, the first trace layer at least partially overlaps the second trace layer, and the shielding trace doesn't overlap the conductive traces.

DETAILED DESCRIPTION

FIG. 1schematically illustrates a top view of a touch panel according to a first embodiment of the present invention, andFIG. 2schematically illustrates a cross-sectional view taken along a line A-A′ ofFIG. 1. As shown inFIG. 1andFIG. 2, the touch panel1has a touch region1T and a trace region1N disposed at least on one side of the touch region1T. The touch region1T may be used for disposing following touch device14to detect the position of touch object, and the trace region1N may be used for disposing following traces, but not limited thereto. In this embodiment, the trace region1N may surround the touch region1T, but not limited thereto. In some embodiments, the touch panel1may be optionally provided with a light shielding layer (not shown) for shielding the traces in the trace region1N. When the touch panel1is applied to a display device, the touch region1T may correspond to a display region of the display device for displaying images, and the trace region1N may correspond to a peripheral region of the display device for disposing peripheral device, but not limited thereto. In this embodiment, the touch panel1may include a substrate12, a touch device14, and a plurality of traces. The substrate12may include, for example, a rigid substrate or a flexible substrate. The rigid substrate may for example include glass or other suitable material, but not limited thereto. The flexible substrate may for example include polyimide (PI) or other suitable materials, but not limited thereto.

The touch device14is disposed on a top surface12S of the substrate12in the touch region1T and used for detecting the position where the user approaches or touches the touch panel1. In this embodiment, the touch device14may be a capacitive touch device, but not limited thereto. Specifically, as shown inFIG. 1andFIG. 2, the touch device14may include a plurality of first electrode pads16E, a plurality of first bridge electrodes16B, a plurality of second electrode pads18E, and a plurality of second bridge electrodes18B. The first bridge electrodes16B may connect the adjacent first electrode pads16E arranged in a first direction D1to each other, so that the first electrode pads16E and the first bridge electrodes16B may be serially connected into a plurality of first electrode strings16extending along the first direction D1. Also, the second bridge electrodes18B may connect the adjacent second electrode pads18E arranged in a second direction D2, so that the second electrode pads18E and the second bridge electrodes18B may be serially connected into a plurality of second electrode strings18extending along the second direction D2. The first direction D1and the second direction D2may respectively be parallel to the top surface12S of the substrate12but not parallel to each other, for example, the first direction D1may be perpendicular to the second direction D2. The first bridge electrode16B may cross and be insulated from the corresponding second bridge electrode18B, such that the first electrode strings16may cross the second electrode strings18to have the capacitive coupling between the first electrode strings16and the second electrode strings18. Accordingly, the position where the user approaches or touches may be detected. For example, when the touch device14is a mutual-capacitance touch device, the first electrode strings16may be used for transmitting driving signals, and the second electrode strings18may be used for transmitting sensing signals, but not limited thereto. The first electrode strings16and the second electrode strings18may be interchanged. In this embodiment, the first electrode pads16E, the second electrode pads18E, and the second bridge electrodes18B may be formed of the same transparent conductive pattern layer TC and thus may include the same transparent conductive material. The transparent conductive material may be, for example, ITO, indium zinc oxide (IZO), antimony tin oxide (ATO), aluminum zinc oxide (AZO), graphene, or other suitable materials, but not limited thereto. The first bridge electrodes16B are formed of the non-transparent conductive pattern layer NC, but not limited thereto. In other embodiments, the first bridge electrodes16B may also be formed of another transparent conductive pattern layer, i.e. the first bridge electrodes16B may include the transparent conductive material. The material of the non-transparent conductive pattern layer NC may include metal, metal alloy, or other suitable non-transparent conductive materials. Moreover, the first bridge electrode16B is disposed between the corresponding second bridge electrode18B and the substrate12, but not limited thereto. In some embodiments, the second bridge electrode18B may be disposed between the corresponding first bridge electrode16B and the substrate12and formed of the non-transparent conductive pattern layer NC, and the first bridge electrodes16B may be formed of the transparent conductive pattern layer TC. In some embodiments, the capacitive touch device may be different from the above structure, for example, the first electrode strings16and the second electrode strings18may be strip-shaped. In some embodiments, the touch device14may be other types of touch devices, such as a resistive touch device.

As shown inFIG. 1andFIG. 2, the traces are disposed on the top surface12S of the substrate12in the trace region1N. The traces may include a plurality of conductive traces and at least one shielding trace. The conductive traces are traces having conductive characteristic other than the shielding trace, and at least a part of the conductive traces is electrically connected to the touch device14. The conductive traces may for example include metal material or be formed of metal material. For example, the conductive traces may include a plurality of first signal traces20and a plurality of second signal traces22, wherein one end of one of the first signal traces20is electrically connected to one end of the corresponding first electrode string16, and one end of one of the second signal traces22is electrically connected to one end of the corresponding second electrode string18, and the other end of the first signal trace20and the other end of the second signal trace22may extend into a pad region26to be electrically connected to different pads (not shown), thereby being further electrically connected to flexible circuit board, control device or other suitable device through the pads. In this embodiment, the first signal traces20and the second signal traces22may be formed of the same non-transparent conductive pattern layer NC and therefore may include the same non-transparent conductive material as the first bridge electrodes16B, but not limited thereto.

The shielding trace may be insulated from the touch device14and may be used for reducing signal interference between different conductive traces. In a direction TD perpendicular to the top surface12S of the substrate12, the shielding trace may be disposed between any two conductive traces and may not overlap the conductive traces. In this embodiment, the traces may include a shielding trace24disposed between the first signal traces20and the second signal traces22and insulated from the touch device14. Since the shielding trace24may for example be a multi-layer structure, the thickness of the shielding trace24is greater than the thicknesses of the first signal traces20and the second signal traces22, so the capacitive coupling doesn't easily penetrate through the shielding trace24to be generated between the first signal traces20and the second signal traces22, thereby reducing the signal interference between the first signal traces20and the second signal traces22. In detail, since the driving method of the touch panel1may be, for example, to transmit the driving signals on the first electrode strings16and to generate the sensing signals on the second electrode strings18through the capacitive coupling between the first electrode strings16and the second electrode strings18, so that the capacitive coupling between the first signal traces20for transmitting the driving signals and the second signal traces22for receiving the sensing signals may easily affect the accuracy of the received sensing signals. Therefore, by disposing the shielding trace24between the first signal traces20and the second signal traces22, the interference between the driving signals and the sensing signals can be reduced. Furthermore, since the first signal traces20are used for transmitting the driving signals and the second signal traces22are used for transmitting the sensing signals, there is no problem of signal interference between any two adjacent first signal traces20and between any two adjacent second signal traces22. Accordingly, the shielding trace24may not be disposed between two adjacent first signal traces20, nor between two adjacent second signal traces22. In one embodiment, the shielding trace24may be electrically connected to ground or be floated. When the shielding trace24is electrically connected to the ground, the shielding trace24may further be used for providing a discharging path of static charges on the first signal traces20and the second signal traces22so as to provide electrostatic discharge (ESD) protection for the touch device14. Since the shielding trace24has the multi-layer structure, the resistance of the shielding trace24may be less than the resistances of the first signal traces20and the second signal traces22, such that the static charges on the first signal traces20and the second signal traces22and the static charges around the shielding trace24may tend to be discharged through the shielding trace24, thereby improving the anti-static ability of the touch panel1.

In this embodiment, the shielding trace24may be a double-layer structure and includes a first trace layer L1and a second trace layer L2, wherein the first trace layer L1is disposed between the substrate12and the second trace layer L2, but not limited thereto. In the direction TD, the first trace layer L1may at least partially overlap the second trace layer L2, so that the first trace layer L1and the second trace layer L2may be electrically connected to each other. In some embodiments, the second trace layer L2may have the same extending length as the first trace layer L1or completely cover the first trace layer L1, but not limited thereto. In the direction TD, the thickness T1of the first trace layer L1in this embodiment is less than the thickness T2of the second trace layer L2. In other embodiments, the thickness T1of the first trace layer L1may be equal to the thickness T2of the second trace layer L2. In the embodiment shown inFIG. 2, the cross-sectional shape of the second trace layer L2may be, for example, a T shape that is a shape having a narrower bottom surface and a wider top surface. For example, the second trace layer L2may include a top portion P1located on the insulating layer IN1and a bottom portion P2penetrating through the insulating layer INL and the bottom portion P2is located between the top portion P1and the first trace layer L1. In a cross-sectional direction, a width W1of the top portion P1may be greater than a width W2of the bottom portion P2. Further, the width W1of the top portion P1may be greater than or equal to the width W3of the first trace layer L1, and the limit of the width W1of the top portion P1is that the projection of the top portion P1on the top surface12S along the direction TD doesn't overlap the first signal trace20and the second signal trace22of the conductive traces closest to the first trace layer L1. For example, the projection of the top portion P1on the top surface12S along the direction TD may have a portion beyond the first trace layer L1and on a side of the first trace layer L1, and the width of the portion may be less than or equal to a half of a distance G between the first trace layer L1and the first signal trace20or the second signal trace22of the conductive traces closest to the first trace layer L1, i.e. the width W1of the top portion P1may comply with the formula: (W1−W3)/2≤G/2.

In some embodiments, the first trace layer L1, the first signal traces20and the second signal traces22may include the same non-transparent conductive material, for example, being formed of the non-transparent conductive pattern layer NC. The non-transparent conductive material may be, for example, a metal material. The second trace layer L2, the first electrode pads16E and the second electrode pads18E may include the same transparent conductive material, for example being formed of the transparent conductive pattern layer TC. Through the second trace layer L2, the first signal traces20and the second signal traces22may be respectively capacitively coupled with the second trace layer L2(as shown by arrow A1inFIG. 2), thereby reducing the signal interference between the first signal traces20and the second signal traces22. In some embodiments, the shielding trace24may be a multilayer structure and include multiple trace layers.

In some embodiments, the conductive traces may optionally further include an anti-static ring28for providing the touch panel1with a static discharging path. The anti-static ring28at least partially surrounds the touch device14, the first signal traces20and the second signal traces22, and the first signal traces20and the second signal traces22may be disposed between the touch device14and the anti-static ring28. For example, as shown inFIG. 1, the anti-static ring28may include two anti-static lines28L1,28L2, and the first signal traces20and the second signal traces22may be respectively disposed between the anti-static line28L1and the touch device14and between the anti-static line28L2and the touch device14. In such situation, the traces may further include a shielding trace30disposed between the anti-static line28L2and the second signal traces22. In some embodiments, as shown inFIG. 2, the shielding trace30may have a structure similar to or the same as the shielding trace24, for example, including the first trace layer L1and the second trace layer L2, and accordingly will not be redundantly detailed. In addition, in the direction TD, the shielding trace30may not overlap the second signal traces22and the anti-static ring28.

In some embodiments, the conductive traces may further include a plurality of third signal traces32respectively electrically connected to the other ends of the first electrode strings16. For example, the third signal traces32may extend to a side of the touch device14opposite to the first signal traces20through a side of the touch device14opposite to the second signal traces22. The third signal traces32and the first signal traces20may for example are respectively connected to the odd first electrode strings16and the even first electrode strings16counted from left to right of the first electrode strings16, but not limited thereto, and they may be exchanged. Alternatively, one of the third signal traces32and a corresponding one of the first signal traces20may be electrically connected to the same first electrode string16, but not limited thereto. In this case, the traces may further include a shielding trace34and a shielding trace36, the shielding trace34is disposed between the first signal traces20and the third signal traces32, and the shielding trace36is disposed between the third signal traces32and the anti-static line28L1. In some embodiments, the shielding trace34and/or the shielding trace36may be similar to or the same as the shielding trace24and have the multilayer structure. In some embodiments, at least one of the shielding traces24,30,34,36may have the multilayer structure, and others may be formed of the non-transparent conductive pattern layer NC. In some embodiments, the conductive traces may further include a plurality of fourth signal traces (not shown) respectively electrically connected to the other ends of the second electrode strings18, and in such situation, the traces may further include a shielded trace (not shown) between the fourth signal traces and the first signal traces20. In some embodiments, the traces may only include at least one of the shielding trace24,30,34,36and doesn't include other shielding traces. For example, the traces may include only the shielding trace24disposed between the first signal traces20and the second signal traces22or the shielding trace30disposed between the second signal traces22and the anti-static line28L2, but not limited thereto.

In this embodiment, the touch panel1may further include an insulating layer IN1disposed between the non-transparent conductive pattern layer NC and the transparent conductive pattern layer TC and used for electrically insulating the first bridge electrode16B from the second bridge electrode18B. The insulating layer IN1may have a plurality of openings OP1exposing the first trace layer L1and two parts of each of the first bridge electrodes16B in the touch region1T, so that the second trace layer L2may be electrically connected to the first trace layer L1through one of the openings OP1, and the first electrode pads16E and the first bridge electrodes16B may be electrically connected into the first electrode strings16. The insulating layer IN1may include silicon oxide, silicon nitride, or other suitable insulating materials. In some embodiments, the touch panel1may optionally include a protection layer PA disposed on the touch device14and the traces to protect them. The protection layer PA may include silicon oxide, silicon nitride, organic materials, or other suitable insulating materials. In some embodiments, the touch panel1may optionally include a cover plate38attached to the protection layer PA to be used as a film of the touch panel1where the user touches. The cover plate38may include, for example, a rigid substrate or a flexible substrate. The rigid substrate may for example include glass, or other suitable material, but not limited thereto. The flexible substrate may include, for example, polyimide (PI) or other suitable materials, but not limited thereto. When the shielding trace (e.g. the shielding trace24) has the multi-layer structure, the distance between the cover plate38and the shielding trace24may be less than the distance between the cover plate38and the signal trace, and therefore the static charges accumulated at the surface of the cover plate38facing the substrate12may tend to be discharged by the shielding trace24(as shown by the arrow A2ofFIG. 2), thereby improving the anti-static ability of the touch panel1. In some embodiments, the cover plate38may include a light-shielding layer for shielding the devices in the trace region1N and define the touch region1T, but not limited thereto.

The manufacturing method of the touch panel1will be further described below. Please refer toFIG. 3, which is a flowchart of a method for manufacturing a touch panel according to an embodiment of the present invention. As shown inFIG. 3, the manufacturing method of the touch panel may include steps S10, S12, S14, S16. The manufacturing method ofFIG. 3will be described below with reference toFIG. 1andFIG. 2of the first embodiment, but not limited thereto. In some embodiments, some steps may be added or deleted according to requirements. As shown inFIG. 1toFIG. 3, in the step S10, the substrate12is firstly provided. Then, the touch device14is formed on the substrate12in the touch region1T, and the shielding trace (e.g. the shielding trace24) is formed on the substrate12in the trace region1N. The first embodiment ofFIG. 1andFIG. 2are taken as an example in the following description for mentioning the method of forming the touch device14and the shielding trace24, but not limited thereto. In the step S12, the non-transparent conductive pattern layer NC is formed on the top surface12S of the substrate12through a photolithography and etching process to form the first trace layer L1of the shielding trace24and the conductive traces. The shielding trace24is disposed between two of the conductive traces. For example, the shielding trace24is disposed between the first signal trace20and the second signal trace22. Later, in the step S14, the insulation layer IN1is formed on the non-transparent conductive pattern layer NC, and the openings OP1are formed in the insulation layer IN1. Following that, in the step S16, the transparent conductive pattern layer TC is formed on the insulation layer IN1through another photolithography and etching process, thereby forming the touch device14and the second trace layer L2of the shielding trace24at the same time. In some embodiments, the protection layer PA and the cover plate28may be sequentially formed on the touch device14and the traces. Since the first trace layer L1of the shielding trace24and the first signal traces20may be formed of the same non-transparent conductive pattern layer NC and the second trace layer L2and the first electrode pads16E of the touch device14may be formed of the same transparent conductive pattern layer TC, such that the disposition of the shielding trace24doesn't increase the manufacturing step and the number of the used masks. In the manufacturing method of this embodiment, since the non-transparent conductive pattern layer NC is formed before forming the transparent conductive pattern layer TC, an alignment step may be performed through the non-transparent conductive pattern layer NC while forming the transparent conductive pattern layer TC, thereby increasing alignment accuracy between the transparent conductive pattern layer TC and the non-transparent conductive pattern layer NC.

The touch panel and the manufacturing method thereof of the present invention are not limited to the above embodiment and may include other embodiments or variant embodiments. In order to simplify the description and highlight the differences between the first embodiment and other embodiments between the first embodiment and variant embodiments, the elements of other embodiments and variant embodiments and the same element of the first embodiment will use the same reference numerals, and the repeated portion will not be redundantly described.

Please refer toFIG. 4, which schematically illustrates a cross-sectional view of a touch panel according to a variant embodiment of the first embodiment of the invention embodiment. The difference between the touch panel1′ of this variant embodiment and the above embodiment shown inFIG. 2is that in this embodiment, the metal mesh layer ML may replace the transparent conductive pattern layer TC of the above embodiment. Specifically, the first electrode pads16E, the second electrode pads18E, the second bridge electrodes18B and the second trace layer L2of the shielding trace24may be formed of the same metal mesh layer ML. Since the metal mesh layer ML has a mesh shape and the widths of the mesh lines are small enough to be hardly noticed by human eyes, the metal mesh layer ML may not affect the images displayed by the combined display device. The metal mesh layer ML may include a metal material, such as silver or nano silver. In some embodiments, the non-transparent conductive pattern layer NC may be a metal mesh layer.

Please refer toFIG. 5andFIG. 6.FIG. 5schematically illustrates a top view of a touch panel according to a second embodiment of the present invention.FIG. 6schematically illustrates a cross-sectional view taken along a line B-B′ ofFIG. 5. The difference between the touch panel2of this embodiment and the above embodiment is that the transparent conductive pattern layer TC of this embodiment is formed on the substrate12before forming the non-transparent conductive pattern layer NC. Specifically, in the manufacturing method of the touch panel2of this embodiment, the transparent conductive pattern layer TC including the first electrode pads16E, the second electrode pads18E and the second bridge electrodes18B is firstly formed on the substrate12, and then, the insulating layer IN1having the openings OP1is formed on the transparent conductive pattern layer TC. Next, the non-transparent conductive pattern layer NC including the first bridge electrodes16B and signal traces is formed on the insulating layer IN1, thereby forming the touch device214and the shielding traces224,230,234,236. In the touch panel2of this embodiment, the second trace layer L2of the shielding trace224formed of the transparent conductive pattern layer TC may be disposed between the substrate12and the first trace layer L1formed of the non-transparent conductive pattern layer NC. Moreover, the second bridge electrodes18B may be disposed between the first bridge electrodes16B and the substrate12, but not limited thereto. In some embodiments, at least one of the shielding traces224,230,234,236may have the multilayer structure and include the first trace layer L1and the second trace layer L2. In some embodiments, the second trace layer L2of at least one of the shielding traces224,230,234,236may be similar to or the same as the second trace layer L2of the first embodiment, and the width relationship between the second trace layer L2and the first trace layer L1may be similar to or the same as the width relationship between the second trace layer L2and the first trace layer L1of the first embodiment and therefore will not be repeated herein. In some embodiments, the transparent conductive pattern layer TC including the first electrode pads16E, the second electrode pads18E, the second bridge electrodes18B, and the second trace layer L2of the shielding trace224may be replaced with the metal mesh layer. In some embodiments, the non-transparent conductive pattern layer NC may be the metal mesh layer.

Please refer toFIGS. 7 and 8.FIG. 7schematically illustrates a top view of a touch panel according to a third embodiment of the present invention.FIG. 8schematically illustrates a cross-sectional view taken along a line C-C′ ofFIG. 7. The difference between the touch panel3of this embodiment and the first embodiment ofFIG. 1andFIG. 2is that the touch device314of this embodiment may be formed of two transparent conductive pattern layer TC1, TC2and the insulating layer IN2. Specifically, in the manufacturing method of the touch panel3of this embodiment, the non-transparent conductive pattern layer NC including the signal traces is firstly formed, and then the insulating layer IN1having the openings OP1is formed on the non-transparent conductive pattern layer NC. Thereafter, the transparent conductive pattern layer TC1is formed on the insulating layer IN1, and the insulating layer IN2having the openings OP2is formed on the transparent conductive pattern layer TC1. Then, the transparent conductive pattern layer TC2is formed on the insulating layer IN2, thereby forming the touch device314and the shielding traces324,330,334,336. In this embodiment, the second electrode strings318formed by connecting the second electrode pads18E and the second bridge electrodes18B may be formed of the transparent conductive pattern layer TC1, and the first electrode strings316formed by connecting the first electrode pads16E and the first bridge electrodes16B may be formed of the transparent conductive pattern layer TC2, but not limited thereto. In some embodiments, the first electrode strings316and the second electrode strings318may be formed of the transparent conductive pattern layer TC1and the transparent conductive pattern layer TC2, respectively. It is noted that the shielding traces324,330,334,336of this embodiment may have a three-layer structure and include the first trace layer L1, the second trace layer L2, and a third trace layer L3. The first trace layer L1may be formed of the non-transparent conductive pattern layer NC, the second trace layer L2may be formed of the transparent conductive pattern layer TC1and is electrically connected to the first trace layer L1through the opening OP1, and the third trace layer L3may be formed of the transparent conductive pattern layer TC2and electrically connected to the second trace layer L2through the opening OP2. In some embodiments, at least one of the shielding traces324,330,334,336may have the multi-layer structure, and the others may be formed of the non-transparent conductive pattern layer NC. In some embodiments, the second trace layer L2and/or the third trace layer L3of at least one of the shielding traces324,330,334,336may be similar to or the same as the second trace layer L2of the first embodiment, and the width relationship between the second trace layer L2and/or the third trace layer L3and the first trace layer L1may also be similar or the same as the width relationship between the second trace layer L2and the first trace layer L1of the first embodiment, so they will not be repeatedly detailed. In some embodiments, the transparent conductive pattern layer TC1including the second electrode pads18E, the second bridge electrodes18B and the second trace layer L2of the shielding trace may be replaced with the metal mesh layer. In some embodiments, the transparent conductive pattern layer TC2including the first electrode pads16E, the first bridge electrodes16B, and the third trace layer L3of the shielding trace may be replaced with the metal mesh layer.

As mentioned above, in the touch panel of the present invention, since the shielding trace is the multilayer structure, the capacitive coupling doesn't easily penetrate through the shielding trace to be generated between the conductive traces (e.g. signal traces), thereby reducing the signal interference between the conductive traces. Also, since the shielding trace has the multilayer structure, the resistance of the shielding trace may be less than the resistances of the conductive traces, so that the static charges on the conductive traces or the cover plate may be preferentially discharged through the shielding trace, thereby improving the anti-static ability of the touch panel.