CN108614652B

CN108614652B - Touch panel

Info

Publication number: CN108614652B
Application number: CN201611145426.1A
Authority: CN
Inventors: 蔡清丰; 罗伟仁
Original assignee: Hexin Photoelectric Co ltd
Current assignee: Hexin Photoelectric Co ltd
Priority date: 2016-12-13
Filing date: 2016-12-13
Publication date: 2021-07-09
Anticipated expiration: 2036-12-13
Also published as: CN108614652A

Abstract

A touch panel comprises a substrate, at least one touch electrode, a control unit and a lead structure. The substrate is provided with a touch sensing area and a peripheral circuit area. The touch electrode is arranged in a touch sensing area of the substrate and comprises a first transparent conductive layer, a second transparent conductive layer and a metal grid layer. The first transparent conductive layer is arranged on the substrate. The second transparent conductive layer is arranged on the first transparent conductive layer. And the metal grid layer is arranged between the first transparent conducting layer and the second transparent conducting layer and at least partially contacts with the first transparent conducting layer and the second transparent conducting layer, wherein the metal grid layer is composed of a plurality of metal wires. The lead structure is arranged in the peripheral circuit area of the substrate and is used for electrically connecting the touch electrode to the control unit. Therefore, the penetration rate and the conductivity of the touch electrode can be improved.

Description

Touch panel

Technical Field

The invention relates to a touch panel.

Background

In recent years, the application of capacitive touch screens to electronic products is becoming popular. The capacitive touch screen works by using current induction of a human body, and is a touch screen which induces a touch signal by combining an electrode and human body characteristics. When a human body (finger) touches the touch screen, a coupling capacitor is formed between the finger and the conductor layer of the touch screen under the action of an electric field of the human body, and current generated by an electrode on the touch screen flows to a contact point, so that the position of a touch point can be accurately calculated.

Generally, a touch panel of a touch screen is a critical part, and the touch panel mainly includes two parts, namely a conductive layer and an insulating substrate. In order to pursue higher brightness, the conductive layer is mainly composed of a transparent conductive material, and is formed on the insulating substrate through a process of vacuum coating and patterned etching. However, the transparent conductive material is composed of oxidized metal, which may have a problem of high resistance.

Disclosure of Invention

In various embodiments of the present invention, the sensing electrode of the touch panel is formed by stacking a transparent conductive material, a mesh-shaped metal conductive material, and a transparent conductive material to increase the transmittance and the conductivity. In some embodiments, the lead or the connecting wire may also have the three-layer structure. In some embodiments, the transparent conductive material may be designed to be mesh-shaped, and the mesh pattern may be the same as the mesh-shaped metal conductive material, so as to save the number of masks in the manufacturing process.

According to some embodiments of the present invention, a touch panel includes a substrate, at least one touch electrode, a control unit, and a lead structure. The substrate is provided with a touch sensing area and a peripheral circuit area. The touch electrode is arranged on the touch sensing area of the substrate and comprises a first transparent conducting layer, a second transparent conducting layer and a metal grid layer. The first transparent conductive layer is arranged on the substrate. The second transparent conductive layer is arranged on the first transparent conductive layer. And the metal grid layer is arranged between the first transparent conducting layer and the second transparent conducting layer and at least partially contacts with the first transparent conducting layer and the second transparent conducting layer, wherein the metal grid layer is composed of a plurality of metal wires. The lead structure is arranged in the peripheral circuit area of the substrate and is used for electrically connecting the touch electrode to the control unit.

In some embodiments of the present invention, the metal lines of the metal grid layer form at least one metal line opening, and the second transparent conductive layer includes at least one second opening corresponding to the metal line opening.

In various embodiments of the present invention, the first transparent conductive layer includes at least one first opening corresponding to the metal line opening.

In various embodiments of the present invention, the first transparent conductive layer is a complete layer.

In various embodiments of the present invention, the metal lines of the metal grid layer form at least one metal line opening, and the first transparent conductive layer includes at least one first opening corresponding to the metal line opening.

In various embodiments of the present invention, the lead structure includes at least one metal lead, and the metal lead and the metal wire of the metal grid layer have the same thickness.

In some embodiments of the present invention, the lead structure includes at least one first transparent lead disposed between the metal lead and the substrate, and the first transparent lead and the first transparent conductive layer have the same thickness.

In some embodiments of the present invention, the lead structure includes at least one second transparent lead, the metal lead is disposed between the second transparent lead and the substrate, and the thickness of the transparent lead is the same as that of the second transparent conductive layer.

In some embodiments of the present invention, the lead structure includes at least one second transparent lead, the metal lead is disposed between the second transparent lead and the substrate, and the second transparent lead and the second transparent conductive layer have the same thickness.

In various embodiments of the present invention, the width of the metal wire is greater than the width of the metal wire of the metal mesh layer.

In various embodiments of the present invention, the number of the touch electrodes is plural, and the touch panel further includes at least one connection structure and at least one bridge structure. The connecting structure is connected between two adjacent touch control electrodes. The bridging structure is connected between the two touch electrodes respectively positioned at the two sides of the connecting structure.

In various embodiments of the present invention, the connection structure includes a transparent connection line, wherein the thickness of the transparent connection line is the same as the thickness of the first transparent conductive layer.

In some embodiments of the present invention, the connection structure includes a transparent connection line and a metal connection line, the transparent connection line is disposed between the metal connection line and the substrate, and the thickness of the transparent connection line is the same as that of the first transparent conductive layer.

In various embodiments of the present invention, the widths of the transparent connection line and the metal connection line are substantially the same.

In various embodiments of the present invention, the connection structure includes a metal connection line, and a width of the metal connection line is greater than a width of the metal line of the metal grid layer.

In various embodiments of the present invention, the lead structure includes at least one metal lead, and the bridge structure includes at least one bridge wire, wherein the metal lead and the bridge wire have the same thickness.

Drawings

FIG. 1A is a schematic top view of a touch panel according to some embodiments of the invention;

FIG. 1B is an exploded view of a touch electrode of the touch panel of FIG. 1A;

FIG. 1C is an enlarged top view of a portion of the touch panel of FIG. 1A;

FIG. 1D is a schematic cross-sectional view taken along line 1D-1D of FIG. 1C;

fig. 2 is a partial cross-sectional view of a touch panel according to some embodiments of the invention.

Fig. 3 is a partial cross-sectional view of a touch panel according to some embodiments of the invention.

FIG. 4 is a schematic cross-sectional view of a portion of a touch panel according to some embodiments of the invention;

FIG. 5 is an enlarged top view of a portion of a touch panel according to some embodiments of the present invention;

FIG. 6 is an exploded view of a touch electrode of a touch panel according to some embodiments of the invention;

FIG. 7 is an exploded view of a touch electrode of a touch panel according to some embodiments of the invention;

FIG. 8 is a schematic top view of a touch panel according to some embodiments of the invention; and

fig. 9 is a schematic top view of a touch panel according to some embodiments of the invention.

Detailed Description

In the following description, for purposes of explanation, numerous implementation details are set forth in order to provide a thorough understanding of the various embodiments of the present invention. It should be understood, however, that these implementation details are not to be interpreted as limiting the invention. That is, in some embodiments of the invention, such implementation details are not necessary. In addition, some well-known and conventional structures and elements are shown in the drawings in a simplified schematic manner for the sake of simplifying the drawings.

Fig. 1A is a schematic top view of a touch panel 100 according to some embodiments of the invention. The touch panel 100 includes a substrate 110, at least one touch electrode 120, a lead structure 130, and a control unit 140. The touch electrode 120 is disposed on the substrate 110. The lead structure 130 is disposed on the substrate 110 and electrically connects the touch electrode 120 to the control unit 140. Here, the control unit 140 and the lead structure 130 can be electrically connected through the flexible circuit board 142, but the scope of the present invention should not be limited thereto, and in other embodiments, the control unit 140 can be directly disposed on the substrate 110 and directly connected to the lead structure 130.

Here, the touch panel 100 is configured with a dual-layer touch electrode. Specifically, in some embodiments of the present invention, the touch electrodes 120 include a touch electrode 120a and a touch electrode 120b, which are respectively arranged along the first direction D1 and the second direction D2. The touch panel 100 further includes at least one connection structure 150 and at least one bridge structure 160. The connecting structure 150 is connected between two adjacent touch electrodes 120 a. The bridging structure 160 is connected between the two touch electrodes 120b respectively located at two sides of the connecting structure 150. The bridging structure 160 includes an insulating block 162 and a bridging conductive line 164. In various embodiments of the present invention, the bridging wire 164 is connected to the two touch electrodes 120b, and the insulating block 162 is disposed between the bridging wire 164 and the connecting structure 150, so that the connecting structure 150 can be connected to the two touch electrodes 120a without electrically connecting the bridging wire 164. In this way, the connecting structure 150 and the touch electrode 120a form an electrode string extending along a first direction D1, and the connecting structure 150 and the touch electrode 120b form an electrode string extending along a second direction D2, wherein the first direction D1 is not parallel to the second direction D2, so that the two electrode strings are staggered. For example, the first direction D1 and the second direction D2 are perpendicular to each other.

Refer to fig. 1A and 1B simultaneously. Fig. 1B is an exploded schematic view of the touch electrode 120 of the touch panel 100 of fig. 1A. The touch electrode 120 (which may be the touch electrode 120a or the touch electrode 120b) includes a first transparent conductive layer 122, a second transparent conductive layer 124, and a metal mesh layer (metal mesh) 126. The first transparent conductive layer 122 is disposed on the substrate 110. The second transparent conductive layer 124 is disposed on the first transparent conductive layer 122. The metal mesh layer 126 is disposed between the first transparent conductive layer 122 and the second transparent conductive layer 124, and at least partially contacts the first transparent conductive layer 122 and the second transparent conductive layer 124, wherein the metal mesh layer 126 is formed by a plurality of metal lines 126a, and the metal lines 126a of the metal mesh layer 126 form at least one metal line opening 126 b. The first transparent conductive layer 122 includes at least one first opening 122a corresponding to the metal line opening 126b, and the second transparent conductive layer 124 includes at least one second opening 124a corresponding to the metal line opening 126 b.

In various embodiments of the present invention, the solid portion of the metal mesh layer 126 (excluding the metal line opening 126b) is at least partially sandwiched between the solid portion of the first transparent conductive layer 122 (excluding the first opening 122a) and the solid portion of the second transparent conductive layer 124 (excluding the second opening 124 a). As a result, a multi-layer stacked configuration can be formed, so that the touch electrode 120 has high transmittance and high conductivity.

In a preferred embodiment, the solid portion of the metal mesh layer 126 (excluding the metal line opening 126b) is designed to be completely sandwiched between the solid portion of the first transparent conductive layer 122 (excluding the first opening 122a) and the solid portion of the second transparent conductive layer 124 (excluding the second opening 124 a). Specifically, the projection of the solid portion of the metal mesh layer 126 on the substrate 110 is completely located within the projection of the solid portion of the first transparent conductive layer 122 on the substrate 110, and the projection of the solid portion of the metal mesh layer 126 on the substrate 110 is completely located within the projection of the solid portion of the second transparent conductive layer 124 on the substrate 110. Thereby, the portion of the touch electrode 120 where the metal mesh layer 126 is disposed is entirely in a multi-layer stacked configuration. For example, the top and bottom surfaces of the solid portion (excluding the metal line opening 126b) of the metal mesh layer 126 are all in contact with the first transparent conductive layer 122 and the second transparent conductive layer 124, respectively.

In some embodiments, the metal mesh layer 126 has a smaller thickness in order to increase the transmittance of the metal mesh layer 126. For example, the thickness T1 of the metal mesh layer 126 is approximately within 50 to 500 angstroms, preferably 50 to 300 angstroms. In some embodiments, the width W1 of the metal lines 126a of the metal mesh layer 126 is within 3 to 20 microns, preferably 3 to 10 microns, or 5 to 10 microns, so as not to sacrifice the conductivity of the metal mesh layer 126.

Fig. 1C is an enlarged top view of a part of the touch panel 100 of fig. 1A. FIG. 1D is a schematic cross-sectional view taken along line 1D-1D of FIG. 1C. Refer to fig. 1C and 1D simultaneously. In some embodiments, the lead structure 130 may also be configured by a multi-layer stack, and in some embodiments, the lead structure 130 includes at least one first transparent lead 132, at least one second transparent lead 134, and at least one metal lead 136. The first transparent wires 132 are disposed between the metal wires 136 and the substrate 110. The metal wires 136 are disposed between the second transparent wires 134 and the substrate 110. Herein, the first transparent wires 132, the second transparent wires 134 and the metal wires 136 of the wire structure 130 are all of a full-surface structure. In other embodiments, at least one of the first transparent wires 132, the second transparent wires 134 and the metal wires 136 of the wire structure 130 may be a mesh structure, and may have openings therein like the touch electrode 120, wherein the openings of the first transparent wires 132, the second transparent wires 134 and the metal wires 136 may overlap and correspond to each other.

In some embodiments, the touch electrode 120 and the lead structure 130 can be fabricated in the same process. Specifically, the metal wires 136 and the metal mesh layer 126 may be formed by patterning the same metal layer L3, and the thickness and material of the metal wires 136 and the metal mesh layer 126 are substantially the same. Similarly, the first transparent wires 132 and the first transparent conductive layer 122 can be formed by patterning the same transparent conductive material layer L1, and the thickness and material of the first transparent wires 132 and the first transparent conductive layer 122 are substantially the same. Similarly, the second transparent wires 134 and the second transparent conductive layer 124 can be formed by patterning the same transparent conductive material layer L2, and the thickness and material of the second transparent wires 134 and the second transparent conductive layer 124 are substantially the same.

For convenience of illustration, the transparent conductive material layer L1 is used to represent the layer body where the first transparent conductive layer 122, the first transparent wire 132 and the first transparent connecting wire 152 are located. The layer body where the second transparent conductive layer 124, the second transparent wire 134 and the second transparent connecting wire 154 are located is represented by a transparent conductive material layer L2. The metal layer L3 represents the layer body where the metal mesh layer 126, the metal wire 136 and the metal connection wire 156 are located. The transparent conductive material layer L1 and the transparent conductive material layer L2 may be made of transparent conductive materials, such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), etc. The metal layer L3 may be made of various metals having good conductivity, such as copper or silver.

It should be appreciated that the lead structure 130 may not be configured in a multi-layer stack configuration, for example, the lead structure 130 may be composed of only the metal leads 136 without the first and second

transparent leads

132 and 134. Alternatively, the lead structure 130 may be composed of only the first transparent leads 132, the second transparent leads 134, or both, without being provided with the metal leads 136. Of course, the scope of the invention should not be limited thereby, and in other embodiments, the lead structure 130 may be formed on the substrate 110 together with the bridge wire 164, as described in detail with reference to the following embodiment of fig. 9.

In various embodiments of the present invention, the connection structure 150 may also adopt a multi-layer stacking configuration. The connection structure 150 includes a first transparent connection line 152, a second transparent connection line 154, and a metal connection line 156. Herein, the first transparent connecting lines 152, the second transparent connecting lines 154 and the metal connecting lines 156 of the connecting structure 150 are all of a full-surface structure. In other embodiments, at least one of the first transparent connection lines 152, the second transparent connection lines 154 and the metal connection lines 156 of the connection structure 150 may be a grid structure, and may have respective openings therein as the touch electrodes 120, wherein the openings of the first transparent connection lines 152, the second transparent connection lines 154 and the metal connection lines 156 may overlap and correspond to each other.

In some embodiments, the touch electrode 120 and the connecting structure 150 can be formed in the same process. Specifically, the first transparent connecting line 152 and the first transparent conductive layer 122 may be formed by patterning the same transparent conductive material layer L1, and the material and the thickness of the first transparent connecting line 152 and the first transparent conductive layer 122 are substantially the same. The second transparent connection line 154 and the second transparent conductive layer 124 can be formed by patterning the same transparent conductive material layer L2, and the material and thickness of the second transparent connection line 154 and the second transparent conductive layer 124 are substantially the same. The metal connection lines 156 and the metal mesh layer 126 may be formed by patterning the same metal layer L3, and the material and thickness of the metal connection lines 156 and the metal mesh layer 126 are substantially the same.

It should be appreciated that the connection structure 150 may not be configured as a multi-layer stack, for example, the connection structure 150 may be composed of only the metal connection lines 156 without the first and second

transparent connection lines

152 and 154. Alternatively, the lead structure 130 may be composed of only the first transparent connection line 152, the second transparent connection line 154, or both, without the metal connection line 156.

Reference is also made to fig. 1B to 1D. In various embodiments of the present invention, the patterned transparent conductive material layer L1, the patterned metal layer L3, and the patterned transparent conductive material layer L2 may be formed by exposure using the same mask. In various embodiments of the present invention, since the same mask is used, the patterns of the first transparent conductive layer 122, the metal mesh layer 126 and the second transparent conductive layer 124 are substantially the same. Specifically, the first openings 122a of the first transparent conductive layer 122, the metal wire openings 126b of the metal mesh layer 126, and the second openings 124a of the second transparent conductive layer 124 have substantially the same vertical projection shape on the substrate 110, and ideally overlap each other, that is, the areas of the first openings 122a, the metal wire openings 126b, and the second openings 124a are ideally equal to each other.

Of course, due to the precision difference in the manufacturing process, in practical configuration, the first opening 122a of the first transparent conductive layer 122, the metal line opening 126b of the metal mesh layer 126 and the second opening 124a of the second transparent conductive layer 124 may be slightly misaligned, which also causes that the solid portion of the metal mesh layer 126 (excluding the metal line opening 126b) may not be completely sandwiched between the solid portion of the first transparent conductive layer 122 (excluding the first opening 122a) and the solid portion of the second transparent conductive layer 124 (excluding the second opening 124 a).

Similarly, the same mask is used, so that the patterns of the first transparent wires 132, the second transparent wires 134 and the metal wires 136 are substantially the same. Specifically, the first transparent wires 132, the second transparent wires 134, and the metal wires 136 have substantially the same projection shape on the substrate 110 and overlap each other. In other words, the widths of the first transparent wires 132, the second transparent wires 134, and the metal wires 136 are substantially the same.

Similarly, the patterns of the first transparent connecting lines 152, the second transparent connecting lines 154 and the metal connecting lines 156 are substantially the same because the same mask is used. Specifically, the first transparent connecting lines 152, the second transparent connecting lines 154 and the metal connecting lines 156 have substantially the same projection shape on the substrate 110 and overlap each other. In other words, the widths of the first transparent connecting lines 152, the second transparent connecting lines 154 and the metal connecting lines 156 are substantially the same.

It should be understood that, in some embodiments, the patterned transparent conductive material layer L1, the patterned metal layer L3 and the patterned transparent conductive material layer L2 may also be formed by exposure using different masks. Alternatively, in some embodiments, only the patterned transparent conductive material layer L1 and the patterned metal layer L3 may be formed by exposure using the same mask, and the patterned transparent conductive material layer L2 may be formed by exposure using different masks.

In some embodiments of the present invention, the first transparent connecting line 152 is connected to the first transparent conductive layer 122, wherein the second transparent connecting line 154 is connected to the second transparent conductive layer 124, and the metal connecting line 156 is connected to the metal mesh layer 126. In practical applications, when the patterned transparent conductive material layer L1, the patterned metal layer L3, and the patterned transparent conductive material layer L2 are exposed by different masks, only one of the first transparent connecting line 152, the second transparent connecting line 154, and the metal connecting line 156 may be disposed to connect to one of the first transparent conductive layer 122, the second transparent conductive layer 124, and the metal mesh layer 126, so as to achieve the purpose of electrical connection.

In some embodiments of the present invention, the insulation block 162 is disposed on the bridging wires 164. The insulating block 162 covers only a portion of the bridging wires 164, and exposes a portion of the bridging wires 164, so that the touch electrodes 120 can be directly formed thereon to be directly electrically connected to the bridging wires 164. In some embodiments, the insulating block 162 may be formed of a suitable insulating material, such as silicon dioxide. In some embodiments, the bridge wire 164 may be formed of a suitable conductive material, such as copper or silver.

In this embodiment, the patterned transparent conductive material layer L1, the patterned metal layer L3, and the patterned transparent conductive material layer L2 may be formed by only one mask. The following description provides several embodiments, in which the same or different masks are used for the patterned transparent conductive material layer L1, the patterned metal layer L3, and the patterned transparent conductive material layer L2 in sequence, and the touch panel 100 of each embodiment has related structural differences.

Fig. 2 is a partial cross-sectional view of a touch panel 100 according to some embodiments of the invention. This embodiment is similar to the embodiment of fig. 1B, with the difference that: in the present embodiment, the bridge structure 160 includes an insulating layer 162' and a bridge wire 164. The insulating layer 162 'completely covers the bridge wires 164, and the insulating layer 162' has through holes 162 ″ for filling a transparent conductive material layer formed later, such as the transparent conductive material layer L1 (specifically, the first transparent conductive layer 122) and the like, so that the first transparent conductive layer 122 is electrically connected to the bridge wires 164.

Other details of the present embodiment are substantially as described in fig. 1B, and are not repeated herein.

Fig. 3 is a partial cross-sectional view of a touch panel 100 according to some embodiments of the invention. This embodiment is similar to the embodiment of fig. 1B, with the difference that: in this embodiment, the insulating block 162 covers the connecting structure 150, and the bridging wires 164 of the bridging structure 160 are located on the insulating block 162. As shown in the figure, the bridging wires 164 can be directly formed on the touch electrodes 120 and directly electrically connected to the touch electrodes 120.

Fig. 4 is a partial cross-sectional view of a touch panel 100 according to some embodiments of the invention. This embodiment is similar to the embodiment of fig. 1B, with the difference that: in the present embodiment, in the multi-layer stacked configuration of the touch electrode 120, the lead structure 130 and/or the connection structure 150 are not in the multi-layer stacked configuration, but only the patterned metal layer L3 is used to form the lead structure 130 and the connection structure 150, that is, the lead structure 130 may only include the metal lead 136 (refer to fig. 1D), and the connection structure 150 may only include the metal connection line 156 (refer to fig. 1D). The design concept of this embodiment is illustrated only with the configuration of the bridge structure 160 on the top and the connection structure 150 on the bottom in fig. 3, it should be understood that the design concept can also be applied to fig. 1D and fig. 2, and the lead structure 130 or/and the connection structure 150 therein does not adopt the multi-layer stack configuration.

Since the lead structure 130 is mainly located in the non-display region of the substrate 110, the lead structure 130 has a small visual impact, and thus it may not be necessary to design a multi-layer stack structure. In some embodiments, the lead structure 130 may be designed to include only the metal lead 136 (refer to fig. 1D). Although not shown, the width of the metal wires of the wire structure 130 may be configured to be approximately equal to the width of the metal wires of the metal mesh layer 126 of the touch electrode 120. In some embodiments, the width of the metal lead of the lead structure 130 is greater than the width of the metal wire of the metal mesh layer 126 of the touch electrode 120, so as to reduce the resistance of the lead structure 130 with only a single metal lead. In other embodiments, the lead structure 130 may only include the first transparent lead 132 or the second transparent lead 134 (refer to fig. 1D), and at this time, the width of the first transparent lead 132 or the second transparent lead 134 (refer to fig. 1D) may be designed to be larger than the width of the mesh (i.e., the transparent conductive wire) of the first transparent conductive layer 122 or the second transparent conductive layer 124 of the touch electrode 120, so as to reduce the resistance value of only a single layer of the first transparent lead 132 or the second transparent lead 134 (refer to fig. 1D).

On the other hand, the connection structure 150 may also have a different configuration from the embodiment shown in fig. 1B. In some embodiments, since the bridge wire 164 is mostly made of opaque conductive material, such as metal, the connection structure 150 has less visual impact, so that the connection structure 150 may not adopt a multi-layer stacked configuration. In addition, the connection structure 150 may include only the metal connection line 156 (refer to fig. 1D). In various embodiments of the present invention, the width of the metal connection lines of the connection structure 150 may be designed to be larger than the width of the metal lines of the metal mesh layer 126 of the touch electrode 120, so as to reduce the resistance of the connection structure 150 with only a single metal connection line. In other embodiments, the connection structure 150 may only include the first transparent connection line 152 or the second transparent connection line 154, and the width of the first transparent connection line 152 or the second transparent connection line 154 (refer to fig. 1D) is designed to be larger than the width of the mesh line (i.e., the transparent conductive line) of the first transparent conductive layer 122 or the second transparent conductive layer 124 of the touch electrode 120, so as to reduce the resistance value of only a single layer of the first transparent connection line 152 or the second transparent connection line 154 (refer to fig. 1D).

In this embodiment, the patterned transparent conductive material layer L1, the patterned metal layer L3, and the patterned transparent conductive material layer L2 may be formed by only two masks. Other details of the present embodiment are substantially as described in fig. 1B, and are not repeated herein.

Fig. 5 is an enlarged top view of a part of the touch panel 100 according to some embodiments of the invention. This embodiment is similar to the embodiment of fig. 1B, with the difference that: in this embodiment, the width W1 of the metal line 126a of the metal mesh layer 126 is smaller than the width W2 of the transparent conductive line of the first transparent conductive layer 122 or the second transparent conductive layer 124. For example, the width W1 of the metal line 126a may be between 2 microns and 5 microns, and the line width W2 of the first transparent conductive layer 122 may be between 5 microns and 10 microns. In other words, the area of the metal wire opening 126b of the metal mesh layer 126 is larger than the area of the first opening 122a of the first transparent conductive layer 122 or the second opening 124a of the second transparent conductive layer 124.

In addition, the width of the metal wire 136 of the wire structure 130 can also be designed to be smaller than the width of the first transparent wire 132 or the second transparent wire 134 of the wire structure 130. The width of the metal connection line 156 of the connection structure 150 may also be designed to be smaller than the width of the first transparent connection line 152 or the second transparent connection line 154 of the connection structure 150.

In this way, when a process variation occurs, the solid portion of the metal mesh layer 126 is easily maintained to be sandwiched between the solid portion of the first transparent conductive layer 122 and the solid portion of the second transparent conductive layer 124, the metal wires 136 are easily and completely sandwiched between the first transparent wires 132 and the second transparent wires 134, and the metal connecting wires 156 are easily and completely sandwiched between the first transparent connecting wires 152 and the second transparent connecting wires 154, which can also improve the overall transmittance of the touch panel.

Fig. 6 is an exploded view of the touch electrode 120 of the touch panel 100 according to some embodiments of the invention. This embodiment is similar to the embodiment of fig. 1B, with the difference that: in this embodiment, the first transparent conductive layer 122 and the second transparent conductive layer 124 are complete layers without openings. In this way, in the touch electrode 120, only the first transparent conductive layer 122 and the second transparent conductive layer 124 are disposed in a partial region, and the multi-layer stacked structure is disposed in another partial region. Since the first transparent conductive layer 122 and the second transparent conductive layer 124 have high transmittance, the conductivity can be increased without affecting the visual effect.

In this embodiment, the first transparent conductive layer 122 and the second transparent conductive layer 124 can be exposed using the same mask, so that the touch electrode 120 can be formed by using only two masks. Other details of this embodiment are substantially as described in the embodiment of fig. 1B, and are not described herein again.

Fig. 7 is an exploded view of the touch electrode 120 of the touch panel 100 according to some embodiments of the invention. This embodiment is similar to the embodiment of fig. 1B, with the difference that: in this embodiment, the first transparent conductive layer 122 is a complete layer without an opening, and the second transparent conductive layer 124 is a mesh. In this way, in the touch electrode 120, only the first transparent conductive layer 122 is disposed in a partial region, and the multi-layer stacked structure is disposed in another partial region. In view of the high transmittance of the first transparent conductive layer 122, the conductivity can be increased without affecting the visual effect.

In this embodiment, the metal mesh layer 126 and the second transparent conductive layer 124 can be exposed using the same mask, so that the touch sensing electrode 120 can be formed by only two masks, and the metal mesh layer 126 and the second transparent conductive layer 124 have the same pattern. Other details of this embodiment are substantially as described in the embodiment of fig. 1B, and are not described herein again.

Fig. 8 is a schematic top view of a touch panel 100 according to some embodiments of the invention. This embodiment is similar to the embodiment of fig. 1A, with the difference that: the present embodiment employs a single-layer touch electrode configuration. The touch panel 100 includes a substrate 110,

touch electrodes

120c and 120d, a lead structure 130, and a control unit 140. The touch electrode 120c is disposed corresponding to the plurality of touch electrodes 120d, for example, a portion of each touch electrode 120d is disposed in the opening O1 of the touch electrode 120 c. Here, the

touch electrodes

120c and 120d are not crossed and insulated from each other.

As mentioned above, each of the

touch electrodes

120c and 120d includes the first transparent conductive layer 122, the second transparent conductive layer 124 and the metal mesh layer 126, and the metal mesh layer 126 is sandwiched between the first transparent conductive layer 122 and the second transparent conductive layer 124. In the present embodiment, the first transparent conductive layer 122 and the second transparent conductive layer 124 are complete layers, and the lead structure 130 is a single-layer metal lead. It should be understood that the scope of the present invention should not be limited thereby, and in some embodiments, the first transparent conductive layer 122 or the second transparent conductive layer 124 may also be a mesh (e.g., the embodiments of fig. 1B or fig. 5 to 7). In some embodiments, the lead structure 130 may be a multi-layer stacked structure. In other embodiments, the touch electrode 120 and the lead structure 130 can be designed by adopting the configuration of the above embodiments.

Other details of this embodiment are substantially as described above and will not be described herein.

Fig. 9 is a schematic top view of a touch panel 100 according to some embodiments of the invention. The touch panel 100 includes a touch sensing area VA and a peripheral circuit area NA, wherein the touch electrode 120, the connecting structure 150 and the bridging structure 160 are disposed in the touch sensing area VA of the touch panel 100, and the lead structure 130 extends from the peripheral circuit area NA of the touch panel 100 to the touch sensing area VA to electrically connect with the touch electrode 120. Herein, the substrate 110 includes a bendable region BR and non-bendable regions NR located at two sides of the bendable region BR, so that the bendable region BR and the touch sensing region VA are at least partially overlapped.

In various embodiments of the present invention, the bendable region BR is suitable for making the bending ranges of R2 to R8. That is, the bendable region BR is suitable for bending with a radius of curvature of 1 to 8 μm. For example, in the preferred embodiment, the bendable region BR of the substrate 110 is adapted to be bent with a radius of curvature of at least 1 micron to 4 microns. In some embodiments, the width of the bendable region BR is about one or more times the radius of curvature of the bending range. For example, if the non-bending regions NR on both sides of the bending region BR are to be folded, the bending region BR needs to be bent by 180 degrees, and the width W3 of the bending region BR is at least larger than the minimum bending radius of curvature of the substrate 110 multiplied by the circumferential ratio (pi).

In various embodiments of the present invention, the touch electrodes 120 and the connecting structures 150 located in the bendable region BR may adopt different configurations than the touch electrodes 120 and the connecting structures 150 located in the non-bendable region NR. Specifically, the touch electrodes 120 located in the bendable region BR may be stacked in multiple layers (i.e., three layers), and the touch electrodes 120 located in the non-bendable region NR may be only disposed with the transparent conductive material, for example, the touch electrodes 120 located in the non-bendable region NR are disposed with the first transparent conductive layer 122 or/and the second transparent conductive layer 124. In addition, although the connection structure 150 in the bendable region BR and the non-bendable region NR is only configured with the first transparent connection line 152 or the second transparent connection line 154, the scope of the present invention should not be limited thereto, and in other embodiments, the connection structure 150 in the bendable region BR may be configured with the aforementioned multi-layer stack configuration (i.e. three-layer configuration), and the connection structure 150 in the non-bendable region NR is configured with only the first transparent connection line 152 or/and the second transparent connection line 154. Herein, the touch electrode 120 and the connection structure 150 in the bendable region BR may be configured according to the above embodiments, and are not described herein again.

The touch electrode 120 and the connecting structure 150 in the bendable region BR are more easily damaged by external force, and thus the electrical conductivity is reduced. In various embodiments of the present invention, the touch electrodes 120 and the connecting structures 150 of the bendable region BR are stacked in multiple layers, so as to improve the electrical conductivity of the touch electrodes 120 and the connecting structures 150 of the bendable region BR and reduce the possibility of damage caused by concave bending without affecting the brightness.

In the present embodiment, the lead structure 130 and the bridge wires 164 are formed on the substrate 110, so that the lead structure 130 is not manufactured together with the touch electrode 120. At this time, the material and thickness of the lead structure 130 and the bridge wire 164 are the same, for example, both are made of metal. Moreover, the lead structure 130 is at least partially disposed between the touch electrode 120 and the substrate 110, so that the touch electrode 120 can electrically connect the flexible circuit board 142 and the control unit 140 through the lead structure 130.

It should be understood that the configurations of the touch electrode 120, the lead structure 130, the connecting structure 150 and the bridging structure 160 in the above embodiments can be combined and matched in any combination, and the drawings should not be construed as limiting the embodiments.

While the present invention has been described with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A touch panel, comprising:

the touch control circuit comprises a substrate, a touch control circuit and a control unit, wherein the substrate is provided with a touch control induction area and a peripheral circuit area;

at least one touch electrode disposed in the touch sensing area of the substrate, wherein the touch electrode comprises:

a first transparent conductive layer disposed on the substrate;

a second transparent conductive layer disposed on the first transparent conductive layer, wherein the first transparent conductive layer and the second transparent conductive layer are complete layers; and

a metal mesh layer disposed between the first transparent conductive layer and the second transparent conductive layer and at least partially contacting the first transparent conductive layer and the second transparent conductive layer, wherein the metal mesh layer is composed of a plurality of metal wires, the first transparent conductive layer has a first portion and a second portion, the first portion of the first transparent conductive layer is covered by the plurality of metal wires, the second portion of the first transparent conductive layer is not covered by the plurality of metal wires, and the second transparent conductive layer covers the first portion and the second portion of the first transparent conductive layer;

a control unit; and

and the lead structure is arranged in the peripheral circuit area of the substrate and is used for electrically connecting the touch electrode to the control unit.

2. The touch panel of claim 1, wherein the lead structure comprises at least one metal lead having a thickness equal to that of the metal wires of the metal mesh layer.

3. The touch panel of claim 2, wherein the lead structure comprises at least a first transparent lead disposed between the metal lead and the substrate, and the first transparent lead has the same thickness as the first transparent conductive layer.

4. The touch panel of claim 3, wherein the lead structure comprises at least one second transparent lead, the metal lead is disposed between the second transparent lead and the substrate, and the second transparent lead and the second transparent conductive layer have the same thickness.

5. The touch panel of claim 2, wherein the lead structure comprises at least one second transparent lead, the metal lead is disposed between the second transparent lead and the substrate, and the second transparent lead and the second transparent conductive layer have the same thickness.

6. The touch panel of claim 2, wherein the width of the metal lead is greater than the width of the metal wires of the metal mesh layer.

7. The touch panel of claim 1, wherein the number of the touch electrodes is plural, and the touch panel further comprises:

the connecting structure is connected between two adjacent touch electrodes; and

and the bridging structure is connected between the two touch electrodes which are respectively positioned at two sides of the connecting structure.

8. The touch panel of claim 7, wherein the connection structure comprises a transparent connection line and a metal connection line, the transparent connection line is disposed between the metal connection line and the substrate, and the thickness of the transparent connection line is the same as that of the first transparent conductive layer.

9. The touch panel of claim 8, wherein the transparent connecting lines and the metal connecting lines have the same width.

10. The touch panel of claim 7, wherein the connection structure comprises a metal connection line, and a width of the metal connection line is greater than a width of the metal line of the metal mesh layer.

11. The touch panel of claim 7, wherein the lead structure comprises at least one metal lead, and the bridge structure comprises at least one bridge wire, wherein the metal lead and the bridge wire have the same thickness.

12. A touch panel, comprising:

at least one first touch electrode disposed in the touch sensing area of the substrate, wherein the first touch electrode comprises:

a first transparent conductive layer disposed on the substrate;

a second transparent conductive layer disposed on the first transparent conductive layer; and

a metal grid layer arranged between the first transparent conducting layer and the second transparent conducting layer and at least partially contacted with the first transparent conducting layer and the second transparent conducting layer, wherein the metal grid layer is composed of a plurality of metal wires;

at least one second touch electrode disposed in the touch sensing area of the substrate, wherein the second touch electrode does not include a metal material;

at least one bridging structure connecting the first touch electrode to the second touch electrode;

a control unit; and

and the lead structure is arranged in the peripheral circuit area of the substrate and is used for electrically connecting the first touch electrode and the second touch electrode to the control unit.