TW202420052A - Capacitive touch panel - Google Patents

Abstract

A capacitive touch panel includes a first substrate, a signal line, a second substrate and a dummy electrode. The signal line is formed on the first substrate. The second substrate is disposed opposite to the first substrate. The dummy electrode is formed on the second substrate and includes a first part, a second part and a third part. The first part completely overlaps the signal line. The second part overlaps with the signal line at least partially or not at all. The third part does not overlap the signal line at all. The first part, the second part and the third part are completely separated.

Description

Capacitive touch panel

The present invention relates to a capacitive touch panel, and in particular to a suspended capacitive touch panel.

Capacitive touch panels are mostly composed of two substrates arranged opposite to each other. However, when the two substrates are offset (for example, due to manufacturing tolerance, assembly tolerance and/or human factors), the conductive layer on the substrate is misaligned, resulting in an increase in stray capacitance and a decrease in sensing sensitivity. Therefore, how to propose an innovative capacitive touch panel to improve the above-mentioned problems is one of the directions that the industry in this field is constantly working on.

Therefore, the present invention proposes a capacitive touch panel that can improve the above-mentioned known problems.

An embodiment of the present invention provides a capacitive touch panel. The capacitive touch panel includes a first substrate, a first signal line, a second substrate and a first dummy electrode. The first signal line is formed on the first substrate. The second substrate is arranged opposite to the first substrate. The first dummy electrode is formed on the second substrate and includes a first part, a second part and a third part. The first part completely overlaps with the first signal line. The second part at least partially overlaps with the first signal line or does not overlap at all. The third part does not overlap with the first signal line at all. The first part, the second part and the third part are completely separated.

In order to better understand the above and other aspects of the present invention, the following embodiments are specifically described in detail with reference to the accompanying drawings:

Referring to FIGS. 1 to 2B, FIG. 1 is a top view of a capacitive touch panel 100 according to an embodiment of the present invention, FIG. 2A is an enlarged schematic diagram of a portion 2A' of the capacitive touch panel 100 of FIG. 1, and FIG. 2B is a schematic diagram of a second substrate 130 and a first dummy electrode 140 of the capacitive touch panel 100 of FIG. 2A. The capacitive touch panel 100 is, for example, a mutual capacitive touch panel.

As shown in FIGS. 1-2B , the capacitive touch panel 100 includes a first substrate 110, at least one first signal line 120, a second substrate 130, at least one first dummy electrode 140, at least one second signal line 150, and at least one second dummy electrode 160. The second substrate 130 is disposed opposite to the first substrate 110. The first signal line 120 and the second signal line 150 are in a strip shape and cross-arranged. This configuration is called a bar-type sensing structure. Compared with the diamond grid sensing structure, the bar-type sensing structure can provide a higher electric field height (for example, the height along the Z axis), which is more suitable for non-contact touch (suspended touch) sensing. The capacitive touch panel 100 is, for example, a suspended mutual capacitance touch panel. The Z-axis direction shown in the figure is, for example, a touch direction of a touch object (eg, a finger or a touch pen) toward the capacitive touch panel 100 .

The first substrate 110 and the second substrate 130 are, for example, light-transmitting substrates, and their materials include, for example, glass, polyethylene terephthalate (PET) or polycarbonate (PC). One of the first substrate 110 and the second substrate 130 can be a touch-side substrate close to the user. The first signal line 120 is, for example, one of a signal transmission line (Tx) and a signal receiving line (Rx), and the second signal line 150 is, for example, the other of the signal transmission line and the signal receiving line. The first signal line 120 can extend along one of the X-axis and the Y-axis, and the second signal line 150 can extend along the other of the X-axis and the Y-axis. In addition, the first signal line 120 and the second signal line 150 can be arranged face to face, and the interval between the first substrate 110 and the second substrate 130 can be filled by a light-transmitting insulating layer (not shown). In addition, the plurality of first signal lines 120 and the plurality of signal lines 150 are interwoven into a plurality of grids N1 (shown in FIG. 1 ). The number of first dummy electrodes 140 and/or the number of second dummy electrodes 160 configured corresponding to one grid N1 may be plural.

As shown in FIGS. 2A and 2B , the first signal line 120 is formed on the first substrate 110. The first dummy electrode 140 is formed on the second substrate 130 and includes a first portion 141, a second portion 142, and a third portion 143. In order to clearly show the relative relationship between the first signal line 120 and the first dummy electrode 140, a first signal line 120 in FIG. 2A is represented by a cross-hatching line, and the first portion 141, the second portion 142, and the third portion 143 of a first dummy electrode 140 in FIG. 2B are represented by cross-hatching lines of different densities, respectively.

As shown in FIGS. 2A and 2B , the first portion 141, the second portion 142 and the third portion 143 are completely separated. The first portion 141 completely overlaps with the first signal line 120. The second portion 142 at least partially overlaps with the first signal line 120 or does not overlap at all. The third portion 143 does not overlap with the first signal line 120 at all. In this way, even if the first substrate 110 and the second substrate 130 are offset (for example, misaligned along the XY plane direction), the overlapping area of the first signal line 120 and the first dummy electrode 140 (looking toward the Z axis) is limited to the first portion 141 and the second portion 142 (not overlapping the third portion 143), which can reduce stray capacitance and thereby increase touch sensitivity.

In driving, an electrical signal can be transmitted sequentially through several signal transmission lines. The electrical signal generates an electric field between the signal transmission line and the signal receiving line. When the touch object approaches the electric field, part of the energy of the electric field is absorbed by the touch object, causing the signal intensity received by the signal receiving line to change. A controller electrically connected to the signal transmission line and the signal receiving line obtains the touched position (coordinates) accordingly. When the electric field intensity generated between the signal transmission line and the signal receiving line is higher (the stray capacitance is lower), the touch is more sensitive.

Since the portion of the first dummy electrode 140 overlapping with the first signal line 120 (the first portion 141 and/or the second portion 142) is isolated from the third portion 143, the electric field energy can be prevented from being absorbed by the third portion 143, thereby maintaining a certain electric field strength between the first signal line 120 and the second signal line 150, thereby improving touch sensitivity.

As shown in FIGS. 2A and 2B, the second portion 142 is located between the first portion 141 and the third portion 143. A first spacing groove S1 is provided between the first portion 141 and the second portion 142. A second spacing groove S2 is provided between the second portion 142 and the third portion 143. A first distance h1 between the first spacing groove S1 and the second spacing groove S2 is substantially equal to or greater than an assembly tolerance of the first substrate 110 and the second substrate 130. Thus, even if the first substrate 110 and the second substrate 130 are assembled with deviations, the first edge 121 of the first signal line 120 and the second spacing groove S2 may not overlap at all. In addition, the first distance h1 is, for example, a distance between one of the two opposite sides of the first spacing groove S1 and one of the two opposite sides of the second spacing groove S2.

As shown in FIGS. 2A and 2B , the second dummy electrode 160 is formed on the second substrate 130 and is arranged opposite to the first dummy electrode 140 (arranged opposite to each other on the same XY plane). The second dummy electrode 160 includes a fourth portion 161, a fifth portion 162, and a sixth portion 163. In order to clearly show the relative relationship between the first signal line 120 and the second dummy electrode 160, a first signal line 120 in FIG. 2A is indicated by a cross-hatching, and the fourth portion 161, the fifth portion 162, and the sixth portion 163 of a second dummy electrode 160 in FIG. 2B are respectively indicated by cross-hatching of different densities.

As shown in FIGS. 2A and 2B , the fourth portion 161, the fifth portion 162, and the sixth portion 163 are completely separated. The fourth portion 161 completely overlaps with the first signal line 120. The fifth portion 162 at least partially overlaps with the first signal line 120 or does not overlap at all. The sixth portion 163 does not overlap with the first signal line 120 at all. In this way, even if the first substrate 110 and the second substrate 130 are offset (for example, misaligned along the XY plane direction), the overlapping area of the first signal line 120 and the second dummy electrode 160 (looking toward the Z axis) is limited to the fourth portion 161 and the fifth portion 162 (not overlapping the sixth portion 163), which can increase the touch sensitivity.

Furthermore, since the portion of the second dummy electrode 160 that overlaps with the first signal line 120 (the fourth portion 161 and/or the fifth portion 162) is isolated from the sixth portion 163, the electric field energy can be prevented from being absorbed by the sixth portion 163, thereby maintaining a certain electric field strength between the first signal line 120 and the second signal line 150, thereby improving the touch sensitivity.

As shown in FIGS. 2A and 2B, the fifth portion 162 is located between the fourth portion 161 and the sixth portion 163. A third spacing groove S3 is provided between the fourth portion 161 and the fifth portion 162, and a fourth spacing groove S4 is provided between the fifth portion 162 and the sixth portion 163. The second distance h2 between the third spacing groove S3 and the fourth spacing groove S4 is substantially equal to or greater than the assembly tolerance of the first substrate 110 and the second substrate 130. In this way, even if the first substrate 110 and the second substrate 130 are assembled with deviation, the second edge 122 of the first signal line 120 and the fourth spacing groove S4 may not overlap at all. The second edge 122 and the first edge 121 are opposite sides of the first signal line 120, respectively.

In one embodiment, the sum of the first distance h1 and the second distance h2 is, for example, the specification assembly tolerance (design assembly tolerance) of the first substrate 110 and the second substrate 130. The first distance h1 is, for example, the upper deviation of the specification assembly tolerance of the first substrate 110 and the second substrate 130, and the second distance h2 is, for example, the lower deviation of the specification assembly tolerance of the first substrate 110 and the second substrate 130.

As shown in FIGS. 2A and 2B , the distance H1 between the first spacing groove S1 and the third spacing groove S3 is substantially equal to the width W1 of the first signal line 120. Thus, if the first substrate 110 and the second substrate 130 are accurately assembled, the first spacing groove S1 and the first edge 121 of the first signal line 120 are substantially overlapped and the third spacing groove S3 and the second edge 122 of the first signal line 120 are substantially overlapped. Even if the first substrate 110 and the second substrate 130 are misassembled, the first edge 121 of the first signal line 120 and the second spacing groove S2 may overlap, but not overlap with the third portion 143 and/or the second edge 122 of the first signal line 120 and the fourth spacing groove S4 may overlap, but not overlap with the sixth portion 163.

In addition, the capacitive touch panel 100 further includes at least one dummy electrode disposed on the first substrate 110 , and the structure, material and/or size of the at least one dummy electrode may be the same as or similar to the first dummy electrode 140 and/or the second dummy electrode 160 .

In one process, a transparent electrode may be first formed on the second substrate 130, wherein the transparent electrode is made of, for example, indium tin oxide (ITO), a conductive polymer (e.g., PEDOT) or nanosilver, and then, laser etching may be used, for example, to cut the transparent electrode to form all first dummy electrodes 140, all second signal lines 150 and all second dummy electrodes 160 as shown in FIG. 2B. Similarly, another transparent electrode may be first formed on the first substrate 110, and then, laser etching may be used, for example, to cut the transparent electrode to form all first signal lines 120 and all dummy electrodes (not shown) as shown in FIG. 2A. The dummy electrode formed on the first substrate 110 may have a structure similar to or the same as the first dummy electrode 140 and/or the second dummy electrode 160, which will not be described in detail. In addition, the width of the laser-formed spacing groove is, for example, between 5 micrometers (um) and 300 um.

Please refer to Figures 3A to 3C, Figure 3A shows a top view of a capacitive touch panel 200 according to another embodiment of the present invention, Figure 3B shows an enlarged schematic diagram of a portion 3B' of the capacitive touch panel 200 in Figure 3A, and Figure 3C shows a schematic diagram of the second substrate 130 and the first dummy electrode 240 of the capacitive touch panel 200 in Figure 3A.

As shown in FIGS. 3A to 3C , the capacitive touch panel 200 includes a first substrate 110, at least one first signal line 220, a second substrate 130, at least one first dummy electrode 240, at least one second signal line 150, and at least one second dummy electrode 260. The second substrate 130 is disposed opposite to the first substrate 110.

The first substrate 110 and the second substrate 130 are, for example, transparent substrates, and their materials include, for example, glass, polyethylene terephthalate, or polycarbonate. One of the first substrate 110 and the second substrate 130 can be a touch-side substrate close to the user. The first signal line 220 is, for example, one of a signal transmission line and a signal receiving line, and the second signal line 150 is, for example, the other of the signal transmission line and the signal receiving line.

The capacitive touch panel 200 has the same or similar features as the capacitive touch panel 100 , except that, for example, the geometric structures of the first signal line 220 , the first dummy electrode 240 , and the second dummy electrode 260 are different in shape from the first signal line 120 , the first dummy electrode 140 , and the second dummy electrode 160 .

As shown in FIG. 3A , compared to the aforementioned first signal line 120, the first signal line 220 of the present embodiment further includes a protrusion 221, and the protrusion 221 is, for example, close to the direction of the second signal line 150. The protrusion 221 is, for example, a cross shape, but can also be a circle, an ellipse, or a polygon, such as a triangle, a rectangle, etc. In addition, similar to the aforementioned capacitive touch panel 100, the first signal lines 220 and the signal lines 150 of the capacitive touch panel 200 of the present embodiment can be interwoven into a plurality of grids (not shown), and the number of the first dummy electrodes 240 corresponding to one grid configuration can be multiple and/or the number of the second dummy electrodes 260 can be multiple.

As shown in FIGS. 3A to 3C , the first signal line 220 is formed on the first substrate 110. The first dummy electrode 240 is formed on the second substrate 130 and includes a first portion 241, a second portion 242, and a third portion 243. In order to clearly show the relative relationship between the first signal line 220 and the first dummy electrode 240, a first signal line 220 in FIG. 3A is represented by a cross-hatching, and the first portion 241, the second portion 242, and the third portion 243 of a first dummy electrode 240 in FIG. 3B are represented by cross-hatching of different densities.

As shown in FIGS. 3A to 3C , the first portion 241, the second portion 242 and the third portion 243 are completely separated. The first portion 241 completely overlaps with the first signal line 220. The second portion 242 at least partially overlaps with the signal line 220 or does not overlap at all. The third portion 243 does not overlap with the first signal line 220 at all. In this way, even if the first substrate 110 and the second substrate 130 are offset, the overlapping area of the first signal line 220 and the first dummy electrode 240 is limited to the first portion 241 and the second portion 242 (not overlapping the third portion 243), which can increase the touch sensitivity.

As shown in FIGS. 3A to 3C , the second dummy electrode 260 is formed on the second substrate 130 and includes a fourth portion 261, a fifth portion 262, and a sixth portion 263. In order to clearly show the relative relationship between the first signal line 220 and the second dummy electrode 260, a first signal line 220 in FIG. 3A is represented by a cross-hatching line, and the fourth portion 261, the fifth portion 262, and the sixth portion 263 of a second dummy electrode 260 in FIG. 3B are represented by cross-hatching lines of different densities.

As shown in FIGS. 3A-3B , the fourth portion 261, the fifth portion 262, and the sixth portion 263 are completely separated. The fourth portion 261 completely overlaps with the first signal line 220. The fifth portion 262 at least partially overlaps with the first signal line 220 or does not overlap at all. The sixth portion 263 does not overlap with the first signal line 220 at all. In this way, even if the first substrate 110 and the second substrate 130 are offset, the overlapping area of the first signal line 220 and the second dummy electrode 260 is limited to the fourth portion 261 and the fifth portion 262 (not overlapping the sixth portion 263), which can increase the touch sensitivity.

As shown in FIGS. 3A-3B, the second portion 242 is located between the first portion 241 and the third portion 243. A first spacing groove S1 is provided between the first portion 241 and the second portion 242. A second spacing groove S2 is provided between the second portion 242 and the third portion 243. A first distance h1 between the first spacing groove S1 and the second spacing groove S2 is substantially equal to or greater than an assembly tolerance of the first substrate 110 and the second substrate 130. Thus, even if the first substrate 110 and the second substrate 130 are assembled with deviations, the first edge 221 of the first signal line 220 and the second spacing groove S2 may not overlap at all. In addition, the first distance h1 is, for example, a distance between one of the two opposite sides of the first spacing groove S1 and one of the two opposite sides of the second spacing groove S2.

As shown in FIGS. 3A and 3B , the fifth portion 262 is located between the fourth portion 261 and the sixth portion 263. A third spacing groove S3 is provided between the fifth portion 262 and the sixth portion 263, and a fourth spacing groove S4 is provided between the fifth portion 262 and the sixth portion 263. A second distance h2 between the third spacing groove S3 and the fourth spacing groove S4 is substantially equal to or greater than an assembly tolerance of the first substrate 110 and the second substrate 130. Thus, even if the first substrate 110 and the second substrate 130 are assembled with deviation, the second edge 222 of the first signal line 220 and the fourth spacing groove S4 may not overlap at all. The second edge 222 and the first edge 221 are opposite sides of the first signal line 220, respectively.

In one embodiment, the sum of the first distance h1 and the second distance h2 is, for example, the specification assembly tolerance (design assembly tolerance) of the first substrate 110 and the second substrate 130. The first distance h1 is, for example, the upper deviation of the specification assembly tolerance of the first substrate 110 and the second substrate 130, and the second distance h2 is, for example, the lower deviation of the specification assembly tolerance of the first substrate 110 and the second substrate 130.

In addition, the capacitive touch panel 200 further includes at least one dummy electrode disposed on the first substrate 110, and its structure, material and/or size may be the same as or similar to the first dummy electrode 240 and/or the second dummy electrode 260. The first dummy electrode 240 and the second dummy electrode 260 may be formed in the same or similar manner as the aforementioned first dummy electrode 140 and the second dummy electrode 160, which will not be described in detail here. Although not shown, the dummy electrode formed on the first substrate 110 may be formed in the same or similar manner as the first dummy electrode 240 and the second dummy electrode 260, which will not be described in detail here.

In summary, an embodiment of the present invention provides a capacitive touch panel, which includes at least one signal line and at least one dummy electrode, wherein a dummy electrode includes a first portion, a second portion, and a third portion separated from each other, wherein the extension path of the first spacing groove between the adjacent first portion and the second portion is substantially parallel to or overlaps with the extension path of one edge of the signal line, and the extension path of the second spacing groove between the adjacent second portion and the third portion is substantially parallel to or overlaps with the extension path of the other edge of the signal line. In this way, the portion of the dummy electrode that overlaps with the signal line is isolated from other portions, thereby preventing the electric field energy from being absorbed by the other portions, thereby allowing the signal line to maintain a certain electric field strength and improving touch sensitivity.

In summary, although the present invention has been disclosed as above by way of embodiments, it is not intended to limit the present invention. A person having ordinary knowledge in the technical field to which the present invention belongs may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope defined in the attached patent application.

100, 200: capacitive touch panel 110: first substrate 120: first signal line 121, 221: first edge 122, 222: second edge 130: second substrate 140, 240: first dummy electrode 141, 241: first portion 142, 242: second portion 143, 243: third portion 150: second signal line 160, 260: second dummy electrode 161, 261: fourth portion 162, 262: fifth portion 163, 263: sixth portion 221: protrusion S1: first spacing groove S2: second spacing groove S3: third spacing groove S4: fourth spacing groove h1: first distance h2: second distance H1: spacing N1: grid W1: width

FIG. 1 shows a top view of a capacitive touch panel according to an embodiment of the present invention. FIG. 2A shows an enlarged schematic diagram of a portion 2A' of the capacitive touch panel of FIG. 1. FIG. 2B shows a schematic diagram of a second substrate and a first dummy electrode of the capacitive touch panel of FIG. 2A. FIG. 3A shows a top view of a capacitive touch panel according to another embodiment of the present invention. FIG. 3B shows an enlarged schematic diagram of a portion 3B' of the capacitive touch panel of FIG. 3A. FIG. 3C shows a schematic diagram of a second substrate and a first dummy electrode of the capacitive touch panel of FIG. 3A.

100: Capacitive touch panel

110: First substrate

120: First signal line

121: The first edge

122: The second edge

130: Second substrate

140: First virtual electrode

141: Part 1

142: Part 2

143: Part 3

150: Second signal line

160: Second virtual electrode

161: Part 4

162: Part 5

163: Part 6

S1: First spacing slot

S2: Second spacing slot

S3: The third interval slot

S4: The fourth interval slot

h1: first distance

h2: Second distance

W1: Width

Claims (10)

A capacitive touch panel includes: a first substrate; a first signal line formed on the first substrate; a second substrate disposed opposite to the first substrate; and a first dummy electrode formed on the second substrate and including: a first portion completely overlapping with the first signal line; a second portion at least partially overlapping with the first signal line or not overlapping at all; and a third portion completely not overlapping with the first signal line; wherein the first portion, the second portion and the third portion are completely separated. A capacitive touch panel as described in claim 1, wherein the second part is located between the first part and the third part. A capacitive touch panel as described in claim 1, wherein there is a first spacing groove between the first part and the second part, and a second spacing groove between the second part and the third part, and a first distance between the first spacing groove and the second spacing groove is substantially equal to or greater than an assembly tolerance of the first substrate and the second substrate. A capacitive touch panel as described in claim 3, wherein the first signal line has a first edge, and the first edge at least partially overlaps with the first spacing groove. A capacitive touch panel as described in claim 3, wherein the first signal line has a first edge, and the first edge at least partially overlaps with the second spacing groove. The capacitive touch panel as described in claim 1 further includes: A second dummy electrode formed on the second substrate and arranged opposite to the first dummy electrode, and including: A fourth portion completely overlapping with the first signal line; A fifth portion at least partially overlapping with the first signal line or not overlapping at all; and A sixth portion completely not overlapping with the first signal line; Wherein, the fifth portion is located between the fourth portion and the sixth portion. A capacitive touch panel as described in claim 6, wherein the fifth part is located between the fourth part and the sixth part. A capacitive touch panel as described in claim 6, wherein there is a third spacing groove between the fourth part and the fifth part, there is a fourth spacing groove between the fifth part and the sixth part, and a second distance between the third spacing groove and the sixth spacing groove is substantially equal to or greater than an assembly tolerance of the first substrate and the second substrate. A capacitive touch panel as described in claim 8, wherein the first signal line has a second edge, and the second edge at least partially overlaps with the third spacing groove or the fourth spacing groove. A capacitive touch panel as described in claim 1, wherein a first spacing groove is provided between the first portion and the second portion, and the capacitive touch panel further comprises: A second dummy electrode formed on the second substrate and arranged opposite to the first dummy electrode, and comprising: A fourth portion completely overlapping with the first signal line; and A fifth portion at least partially overlapping with the first signal line or not overlapping at all; wherein a third spacing groove is provided between the fourth portion and the fifth portion, and a distance between the first spacing groove and the third spacing groove is substantially equal to a width of the first signal line.

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