TWI711955B - Touch panel - Google Patents

Abstract

A touch panel is disclosed. A peripheral circuit region comprising the plurality of traces, each of the plurality of traces is electrically connected to the plurality of first axial sensing electrode units of a touch sensing layer. The plurality of first conductive pads located in a bonding region, and the plurality of first conductive pads are electrically connected to the traces. The plurality of second axial sensing electrode units of the touch sensing layer are electrically connected to the plurality of second conductive pads of the bonding region, and the first conductive pads and the second conductive pads are staggered. Not only can the number of traces be reduced, but also the conductive pad method can be made directly in the joint area, which can effectively save design space and realize the effect of extremely slim boarder.

Description

Touch panel

The present invention relates to a touch panel, which refers to a touch panel with a slim boarder.

In recent years, touch technology has been widely used in various multimedia electronic products, especially portable mobile products, such as smart phones, e-books, or tablet computers. Using touch technology as an input method can effectively replace the existing keyboard or mouse input methods. In addition to improving convenience, but also due to the intuitive operation, touch input technology has become a very popular human-machine interface and multimedia Interactive way.

Continuing with the rapid development of touch technology, the quality of touch devices continues to improve. Especially with the current demand trend of touch devices requiring light, thin and large screens, how to increase the screen utilization rate of touch devices is a very important topic. 1. For example, smart phones with narrow sides and wide designs have become the direction of research and development efforts by various industries. However, the frame width of the touch device depends on the manufacturing process of the conductive circuit, such as printing, laser, yellow light and other manufacturing processes, and the line width and pitch of the fine conductive circuit has also reached a bottleneck. Of course, there are other narrow frame designs. For example, as shown in Figure 1, it is a schematic diagram of a prior art capacitive touch panel. The capacitive touch panel has a touch sensing area 10 and a peripheral circuit area 12. The touch sensing area 10 has multiple sensing units 102 in the X-axis direction and multiple sensing units 104 in the Y-axis direction. A plurality of first fan-out lines 14 and a plurality of second fan-out lines 16 are arranged in the peripheral circuit area, and are respectively electrically connected to a plurality of sensing units 102 in the X-axis direction, mainly for these first fan-out lines The lines 14 and the second fan-out lines 16 are arranged on different planes, and the projections on the substrate are at least partially overlapped, so as to reduce the width of the peripheral circuit area and achieve the purpose of narrow frame.

However, the above-mentioned narrow frame design still has many disadvantages. For example, several first fan-out lines 14 and several second fan-out lines 16 respectively extend to an extension circuit area 18 and are grouped together, and are connected in the Y-axis direction. The wires of the plurality of sensing units 104 extend to the extended circuit area 18 and are grouped together. Finally, the grouped together a number of first fan-out lines 14, a number of second fan-out lines 16, and a number The wires are respectively connected to the conductive pads. This method not only makes the area on both sides of the peripheral circuit area 12 extremely limited, but even the lower part of the peripheral circuit area 12 cannot be designed with any narrow sides due to the need for sufficient overlap area. The narrow bezel technology has been tested; therefore, how to reduce the area of the trace distribution so as to improve the space utilization rate of the touch area is an urgent problem to be solved.

In view of this, the present invention addresses the above-mentioned shortcomings of the prior art and proposes a touch panel to effectively overcome the above-mentioned problems.

The main purpose of the present invention is to provide a touch panel, which utilizes the bonding area to fabricate the conductive pads of the touch driving electrodes and the touch sensing electrodes in a staggered manner, and only one of the touch driving electrodes or the touch sensing electrodes One has a wiring design, which not only makes the total number of wiring designs more simplified, but also greatly increases the space utilization rate to achieve the effect of a very narrow frame.

The secondary objective of the present invention is to provide a touch panel, which uses a ground wire to surround the peripheral circuit area, the touch sensing layer and the bonding area inside, and then electrically connects to the conductive pad of the bonding area. The design allows a ground wire between the conductive pad in the bonding area and the sensing circuit (sensor OD), and the distance between the two is less than or equal to 150um. The ground wire completely covers all traces to achieve good antistatic effect.

In order to achieve the above objective, the present invention provides a touch panel including a touch sensing layer, a peripheral circuit area and a bonding area. The touch sensing layer has a plurality of first-axis sensing electrode units and a plurality of second-axis sensing electrode units that are insulated from each other; the peripheral circuit area includes a plurality of wires, which are electrically connected to the first axes, respectively Sensing electrode unit; the bonding area includes a plurality of first conductive pads and a plurality of second conductive pads arranged alternately, the first conductive pads are electrically connected to the traces, and the second conductive pads are electrically connected Connected to these second axial sensing electrode units.

Wherein, the peripheral circuit area further includes a ground wire, and the bonding area further includes a third conductive pad. The ground wire connects the touch sensing layer, the traces, the first conductive pads, and the second conductive pads. After the pad ring is set inside, it is electrically connected to the third conductive pad to cover the entire wiring range to achieve a good antistatic effect.

Wherein, the first conductive pads, the second conductive pads, and a third conductive pad located in the bonding area are connected to a flexible circuit board by an anisotropic conductive film. There are a plurality of conductive gold balls in the film.

Among them, the touch panel further includes one or more organic or inorganic transparent insulating layers covering the touch sensing layer, these traces and a ground wire. The total thickness of the insulating layer is less than 10um, and the diameter of each conductive gold ball It is greater than the total thickness of the insulating layer to allow electrical conduction of vertical joints.

Among them, the touch panel further includes a substrate. The touch sensing layer, the peripheral circuit area and the bonding area are located on the substrate; the substrate further has a light shielding layer, and the peripheral circuit area and the bonding area are located between the light shielding layer and the substrate. The control sensing layer is the area exposed by the light shielding layer.

Wherein, the first axis sensing electrode units intersect with the second axis sensing electrode units, each first axis sensing electrode unit has a plurality of first sensing electrodes, and each second axis The sensing electrode unit has a plurality of second sensing electrodes, and the first sensing electrodes and the second sensing electrodes are mutually insulated and spaced apart. The touch sensing layer further includes a plurality of bridge structures. Each bridge structure is connected between two adjacent first sensing electrodes. Each bridge structure has two insulating blocks and a connecting line. The two insulating blocks are respectively It is arranged on two adjacent first sensing electrodes, and the connecting line crosses the two insulating blocks to be electrically connected to two adjacent second sensing electrodes.

Wherein, a ground wire is further provided between the first sensing electrodes and the second sensing electrodes, which can avoid the problem of signal interference.

The above description can only be used to illustrate the problem to be solved by the present invention, the technical means to solve the problem, and the effects produced by it, etc. The specific details of the present invention will be described in detail in the following embodiments and related drawings.

The present invention is eager to improve and innovate, and after years of painstaking research, a touch panel has been developed, which can break through the bottleneck of the existing narrow frame design. Hereinafter, multiple embodiments of the present invention will be disclosed in the form of drawings. For clear description, many practical details will be described in the following description. However, it should be understood that these practical details should not be used to limit the present invention. That is to say, in the embodiments of the present invention, some conventionally used structures and elements will be shown in a simple schematic manner in the drawings. It.

Please refer to Figure 2, which is a bottom view of the touch panel of the present invention. The touch panel includes a touch sensing layer 20, a peripheral circuit area 22 and a bonding area 24. The touch panel further includes a substrate 26. For example, the material of the rigid substrate can be glass, strengthened glass, sapphire glass, ceramic or other suitable materials, and the material of the flexible substrate can be selected from polyether sulfide (PES), polyethylene naphthalate Ethanol ester (PEN), polyethylene (PE), polyimide (PI), polyvinyl chloride (PVC), polyethylene terephthalate (PET), etc., which can be changed according to actual design requirements Therefore, the present invention is not limited to this. The touch sensing layer 20, the peripheral circuit area 22 and the bonding area 24 are located on the substrate 26. The substrate 26 further has a light-shielding layer 28, the peripheral circuit area 22 and the bonding area 24 are located between the light-shielding layer 28 and the substrate 26, and the touch sensing layer 20 is the area exposed by the light-shielding layer 28; in other words, the light-shielding layer 28 It can cover the periphery of the substrate 26, the peripheral circuit area 22 and the bonding area 24 can be an annular area where the light shielding layer 28 is located, and the touch sensing layer 20 can be a rectangular area surrounded and exposed by the light shielding layer 28. The light-shielding layer 28 of this embodiment must have sufficient light-shielding properties (that is, OD, Optical Density, value above 3.0). The material of the light-shielding layer 28 can be photoresist, ink, diamond-like carbon, ceramic, or a combination of the above materials. The present invention does not limit the material and shape of the light-shielding layer 28, which can be appropriately changed according to actual design requirements.

Wherein, the touch sensing layer 20 is made of a transparent conductive material, and its material can be indium tin oxide, indium zinc oxide, aluminum tin oxide, aluminum zinc oxide, indium germanium zinc oxide, or other suitable materials. A stacked layer of oxide or at least two of the foregoing, but the present invention is not limited thereto. The touch sensing layer 20 has a plurality of first axis sensing electrode units 30 and a plurality of second axis sensing electrode units 32 which are insulated from each other; these first axis sensing electrode units 30 can be along the X-axis direction The extended sensing electrode series, the second axial sensing electrode units 32 may extend along the Y-axis direction. Wherein, each first axis sensing electrode unit 30 has a plurality of first sensing electrodes 302, and each second axis sensing electrode unit 32 has a plurality of second sensing electrodes 322, and the first sensing electrode 302 is used as a touch drive electrode (Tx), the second sensing electrode 322 is used as a touch sensing electrode (Rx), and the first sensing electrodes 302 and the second sensing electrodes 322 are insulated from each other Interval settings. The touch sensing layer 20 further includes a plurality of bridge structures 34. Each bridge structure 34 is connected between two adjacent first sensing electrodes 302. Each bridge structure 34 has two insulating blocks 342 and a connecting wire. 344. Two insulating blocks 342 are respectively disposed on two adjacent first sensing electrodes 302, and a connecting line 344 spans the two insulating blocks 342 to be electrically connected to two adjacent second sensing electrodes 302. Wherein, the connecting wires 344 in the bridge structure 34 are all conductive materials, which can be transparent conductive materials, such as one or more of indium tin oxide (ITO) and aluminum oxide zinc (AZO); or these connections The material of the wire 344 is metal, which can be selected from at least one of aluminum, silver, gold, tungsten, zinc, copper, indium, manganese, molybdenum, nickel, palladium, platinum, titanium, chromium, cobalt and neodymium, but the present invention does not Limit this. When the driving circuit inputs a driving signal to the first sensing electrodes 302, a corresponding sensing signal is also generated on each second sensing electrode 322. When a touch occurs, the touch point will produce electrode discharge, the dielectric constant between the electrodes and other phenomena, which will cause the capacitance there to also change. Therefore, when the corresponding first sensing electrode 302 is scanned , The sensing signal on the second sensing electrode 322 corresponding to the touch point will also change, so that the touch position can be determined and the touch can be realized.

Wherein, a ground wire (not shown in the figure) is further provided between the first sensing electrodes 302 and the second sensing electrodes 322. In order to avoid signal interference, this can be changed according to actual design requirements. The present invention is not limited to this.

Subsequently, the peripheral circuit area 22 includes a plurality of wires 222 electrically connected to the first sensing electrodes 302 of the first axis sensing electrode units 30 respectively. The material of these traces 222 can be silver (Ag), copper (Cu), aluminum (Al), gold (Au), nickel (Ni), molybdenum (Mo), indium (In), tin (Sn) or titanium (Ti). Similarly, the wiring 222 can be formed by forming a conductive layer on the substrate 26 in advance by a deposition process, and then patterning the conductive layer by photolithography according to the desired layout to obtain these traces. Line 222, but the present invention is not limited to this. The bonding area 24 includes a plurality of first conductive pads 242 and a plurality of second conductive pads 244 alternately arranged. The first conductive pads 242 are electrically connected to the traces 222, and the second conductive pads 244 are electrically connected to the traces 222. The second sensing electrode 322 of the second axial sensing electrode unit 32 is electrically connected.

Since current touch products need to arrange grounding wires at the outermost periphery of the sensing unit, to protect against electrostatic discharge (ESD) or line interference and other problems, to achieve the purpose of noise reduction. However, the grounding wire is only arranged in a part of the wiring range, and is not completely covered. Therefore, the problems of Electrostatic Discharge (ESD) or line interference cannot be effectively improved; therefore, the touch panel design of the present invention A breakthrough improvement has been made in the above, that is, the peripheral circuit area 22 further includes a ground wire 36, and the bonding area 24 further includes a third conductive pad 246. The ground wire 36 connects the touch sensing layer 20 and these traces 222 After the first conductive pads 242 and the second conductive pads 244 are ringed inside, they are electrically connected to the third conductive pads 246 to cover the entire wiring range to achieve good antistatic effect.

In order to further explain that the present invention can solve the technical bottleneck of the existing narrow frame, please refer to FIG. 3, which is a schematic diagram of an embodiment of the bonding area of the present invention. In the present invention, the third conductive pads 246 in the bonding area 24 are located in the area where the plurality of first conductive pads and the plurality of second conductive pads are alternately arranged, and are arranged alternately in the X-axis direction, and the third conductive pads 246 are located there. Arrange the middle position of the staggered arrangement. For example, taking the third conductive pad 246 as the center point position, the intersecting positions of the plurality of first conductive pads TX1, TX2, TX3 and the plurality of second conductive pads RX1, RX2 on the left side of the third conductive pad 246 are It appears as an arrangement of TX1, RX1, TX2, RX2, and TX3; and the staggered position of the plurality of first conductive pads TX4, TX5, TX6 and the plurality of second conductive pads RX3, RX4 on the right side of the third conductive pad 246 It appears as an arrangement of TX4, RX3, TX5, RX4, TX6. Wherein, they are electrically connected to the traces, and the plurality of second conductive pads are arranged alternately. For example, the plurality of first conductive pads TX1, TX2, TX3 are correspondingly electrically connected to the plurality of traces R1, R2. , R3 to these first sensing electrodes, which are used as touch drive electrodes (Tx), while RX1 and RX2 do not need to be designed for wiring, and are directly connected to the second sensing electrodes 322 through electrical bonding, which serve as touch sensing electrodes ( Rx) conduction; in the same way, the plurality of first conductive pads TX4, TX5, TX6 correspond to the plurality of traces R3, R4, R5 electrically connected to the right to the first sensing electrodes on the right, which act as contact The driving electrodes (Tx) are controlled, and RX1 and RX2 do not need to be wired, and are directly connected to the second sensing electrode 322 through electrical bonding, which is used as the touch sensing electrode (Rx) to conduct. From this, it can be seen that the design method of the present invention for narrowing the edges of the bonding area can indeed make the design flexible and save the wiring design space, and also make the 3D wiring technology easier to implement in the film (Film) manufacturing process.

Wherein, the staggered arrangement of the plurality of first conductive pads and the plurality of second conductive pads can be multiple patterns, for example, the first conductive pad is Tx, and the second conductive pad is Rx, except for the above-mentioned Tx, Rx, Tx, In addition to the staggered arrangement of Rx and Tx, it can also be Tx, Rx, Rx, Tx, Rx, Rx, Tx, or Tx, Rx, Rx, Tx, Rx, Tx, Rx, Rx, Tx, etc. In this way, there must be at least one Tx line between two adjacent Rx. Therefore, as long as the plurality of first conductive pads and the plurality of second conductive pads are arranged in a staggered arrangement, they should be included in the scope of the patent application of the present invention.

As shown in Fig. 4A, it is a schematic diagram of Fig. 2 along the line A-A' before joining. The touch panel further includes one or more organic or inorganic transparent insulating layers 38 covering the touch sensing layer 20, the traces 222 and a ground wire 36, and the total thickness of the insulating layer 38 is less than 10um. The first conductive pads, the second conductive pads, and a third conductive pad located in the bonding area are connected to a flexible circuit board with an anisotropic conductive film 40 to conduct electricity. There are a plurality of conductive gold balls 402 in 40. The ground wire 36 is located between the junction area and a sensing circuit (not shown), and the distance (h) between the ground wire 36 and the sensing circuit (sensor OD) is less than or equal to 150um. Cover all traces to achieve a good antistatic effect. As shown in Figure 4B, it is a schematic view of Figure 2 after joining along the A-A' section line. The flexible circuit board 42 is bonded to the first conductive pads through the anisotropic conductive film 40, and the second conductive pads are electrically connected. It is especially important to note that the diameter of each conductive gold ball 402 is larger than that of the insulating layer. The total thickness of 38 (y) can be connected vertically and electrically conductive.

In summary, in the conventional bonding area, the traces of the multiple sensing units in the X-axis direction and the multiple sensing units in the Y-axis direction are clustered in one area, and then they are uniformly connected to the lead conductive pads. The method occupies a large marginal space of the touch product; in addition, the ground wire only protects the wiring, but the conductive pad area in the junction area does not have any protection, and the antistatic effect is poor. In contrast, the present invention uses a ground wire to loop the peripheral circuit area, the touch sensing layer and the bonding area inside, and then electrically connect them to the conductive pads of the bonding area. This design allows the conductive connection of the bonding area There is a grounding wire between the pad and the sensing circuit (sensor OD), and the distance between the two is less than or equal to 150um. The grounding wire can completely cover all the wires to achieve a good antistatic effect. Furthermore, the bonding area is used to make conductive pads in which the touch driving electrodes and the touch sensing electrodes are interleaved, and only one of the touch driving electrodes or the touch sensing electrodes has a wiring design, which not only allows The total number of wiring design is more refined and simplified, and the space utilization rate can be greatly increased to achieve the effect of a very narrow frame, which has a great market competitive advantage.

Only the above are merely preferred embodiments of the present invention, and are not used to limit the scope of the present invention. Therefore, all equivalent changes or modifications made in accordance with the characteristics and spirit of the application scope of the present invention shall be included in the patent application scope of the present invention.

10 Touch sensing area 12 Peripheral route area 102 Sensing unit 104 sensing unit 14 First fanout line 16 Second fanout line 18 Extension circuit area 20 Touch sensing layer 22 Peripheral route area 222 Wiring 24 Joint zone 242 First conductive pad 244 second conductive pad 246 Third conductive pad 26 Substrate 28 shading layer 30 first axis sensing electrode unit 302 First sensing electrode 32 second axial sensing electrode unit 322 second sensing electrode 34 Bridge structure 342 Insulation Block 344 connection line 36 Ground wire 38 Insulation layer 40 Anisotropic conductive film 402 conductive gold ball 42 Flexible circuit board

Figure 1 is a bottom view of a prior art capacitive touch panel. Figure 2 is a bottom view of the touch panel of the present invention. Figure 3 is a schematic diagram of an embodiment of the junction area of the present invention. Fig. 4A is a schematic view of Fig. 2 along the line A-A' before joining. Figure 4B is a schematic view of Figure 2 after joining along the line A-A'.

20 Touch sensing layer 22 Peripheral route area 222 Wiring 24 Junction area 242 First conductive pad 244 second conductive pad 246 Third conductive pad 26 Substrate 28 shading layer 30 first axis sensing electrode unit 302 First sensing electrode 32 second axial sensing electrode unit 322 Second sensing electrode 34 Bridge structure 342 Insulation Block 344 connection line 36 Ground wire

Claims (9)

A touch panel includes: a touch sensing layer with a plurality of first axial sensing electrode units and a plurality of second axial sensing electrode units insulated from each other; a peripheral circuit area including a plurality of wires, Are respectively electrically connected to the first axial sensing electrode units; and a bonding area including a plurality of first conductive pads and a plurality of second conductive pads arranged alternately, the first conductive pads are electrically connected to The traces, the second conductive pads are electrically connected to the second axial sensing electrode units; wherein, the peripheral circuit area further includes a ground wire, and the bonding area further includes a third conductive pad , The ground wire is ringed inside the touch sensing layer, the wires, the first conductive pads, and the second conductive pads to completely cover the wires. Is electrically connected to the third conductive pad. The touch panel according to claim 1, wherein the ground wire is located between the bonding area and a sensing circuit, and the distance between the ground wire and the sensing circuit is less than or equal to 150um. The touch panel according to claim 1, wherein a difference between the first conductive pads, the second conductive pads, and a third conductive pad located in the bonding area and a flexible circuit board The square conductive film is electrically connected, and the anisotropic conductive film has a plurality of conductive gold balls. The touch panel according to claim 4, further comprising one or more organic or inorganic transparent insulating layers covering the touch sensing layer, the wires and a ground wire, and the total thickness of the insulating layer is less than 10um , The diameter of each conductive gold ball is greater than the total thickness of the insulating layer. The touch panel according to claim 1, further comprising a substrate, and the touch sensing layer, the peripheral circuit area and the bonding area are located on the substrate. The touch panel according to claim 5, wherein the substrate further has a light-shielding layer, and the peripheral line The road area and the bonding area are located between the light shielding layer and the substrate, and the touch sensing layer is an area exposed by the light shielding layer. The touch panel according to claim 1, wherein the first axis sensing electrode units intersect the second axis sensing electrode units, and each of the first axis sensing electrode units has a plurality of A sensing electrode, each of the second axial sensing electrode units has a plurality of second sensing electrodes, and the first sensing electrodes and the second sensing electrodes are mutually insulated and spaced apart. The touch panel according to claim 7, wherein the touch sensing layer further includes a plurality of bridge structures, each of the bridge structures is connected between two adjacent first sensing electrodes, each of the The bridge structure has two insulating blocks and a connecting line. The two insulating blocks are respectively disposed on two adjacent ones of the first sensing electrodes. The connecting line crosses the two insulating blocks to electrically connect to two adjacent ones.的 these second sensing electrodes. The touch panel according to claim 7, wherein a ground wire is further provided between the first sensing electrodes and the second sensing electrodes.

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