TWI679572B - Touch electrode pattern and touch display device using the same - Google Patents

Abstract

A touch electrode pattern used in a touch display has a plurality of sensing electrodes provided on a first conductive film, and each of the sensing electrodes is provided with a plurality of first compensation electrodes at intervals; a plurality of driving An electrode is provided on a second conductive film, and a plurality of second compensation electrodes are arranged on each of the driving electrodes at intervals; and an insulating layer is provided between the first conductive film and the second conductive film; wherein, The plurality of sensing electrodes and the plurality of driving electrodes are intersected through the insulating layer to form a plurality of hollow areas, and there are two opposing first compensation electrodes and Two opposing said second compensation electrodes.

Description

Touch electrode pattern and touch display device using the same

The invention relates to a touch electrode pattern of a touch screen, in particular to a touch electrode pattern of an ultra-thin touch screen.

Today, technology is changing rapidly, and touch screens have been widely used in electronic devices to replace traditional screens. In general, the mainstream touch electrode patterns of mutual-capacitive touch screens mainly include single-layer multi-point, indium tin oxide layer bridge (SITO), and double-layer indium tin oxide (DITO). The single-layer multi-point feature is that it can be ultra-thin design and low cost, but there will be blind spots and low touch accuracy; the characteristics of indium tin oxide layer bridge is that it can be ultra-thin design, but the cost is high, and the metal bridge It will be seen in the window area and affect the screen display effect; and, the characteristics of the double-layer indium tin oxide structure are: 1. The indium tin oxide layer (ITO) is divided into two layers, and the general induction electrode is distributed in the upper layer of indium tin oxide layer. The driving electrodes are distributed in the lower indium tin oxide layer; 2. The two layers of indium tin oxide are separated by glass, high-temperature polyester film (PET film) or optical transparent glue (OCA) and other materials. Its advantages are moderate cost and accurate touch It has a high degree, and its disadvantage is that the mutual capacitance value is too large when it is applied to an ultra-thin touch screen.

In order to meet the market demand, touch products are paying more and more attention to thin and light settings. In the case of thin products, each part needs to be compressed as much as possible. In other words, if the pattern design of the double-layer indium tin oxide is adopted, the separator between the upper and lower two layers of indium tin oxide needs to be thinned. However, as the distance between the upper and lower indium tin oxide layers approaches, the capacitance value between the sensing electrode and the driving electrode will increase accordingly, and an excessive capacitance value will cause data saturation and affect the resistance of the touch product. Noise ability.

Please refer to FIG. 1 and FIG. 2 together, which are a schematic diagram of a conventional double-layer indium tin oxide electrode pattern and a copper pillar simulated touch diagram of the electrode pattern, respectively. As shown in FIG. 1 and FIG. 2, a conductive layer including a plurality of sensing electrodes 10 is spaced apart from another conductive layer including a plurality of driving electrodes 11, and a gap 12 is provided between any two adjacent sensing electrodes 10. . Therefore, when the two conductive layers are close to each other, the capacitance value between a sensing electrode 10 and a driving electrode 11 will increase correspondingly. Table 1 describes the change of the capacitance value generated by the touch panel when a copper pillar 13 simulates a finger touching the touch panel.

Table 1 Induction thickness (mm) Initial mutual capacitance value (pF) Capacitance after placing a copper pillar (pF) Capacitance change (pF) Proportion of change (%) 0.55 1.40 1.07 0.33 23.55% 0.4 1.70 1.35 0.35 20.43% 0.3 2.02 1.67 0.35 17.48% 0.2 2.61 2.25 0.36 13.65% 0.1 4.24 3.89 0.35 8.36% 0.05 7.36 7.00 0.36 4.89%

The inductive thickness refers to the vertical distance between an inductive electrode 10 and a driving electrode 11 (induction thickness is needed to reduce the thickness of a touch panel), and its unit is mm; the initial mutual capacitance value is The mutual capacitance value between a sensing electrode 10 and a driving electrode 11 when there is no touch operation, the unit is pF; the capacitance value after placing the copper pillar refers to the value generated after touching the touch panel with a copper pillar 13 The capacitance value is in units of pF; the capacitance change value refers to the amount of capacitance change before and after the touch, and the unit is pF; the percentage of the change amount refers to the ratio of the capacitance change value to the initial mutual capacitance value.

It can be known from Table 1 that the conventional conventional electrode pattern is only applicable to a case where the distance between two conductive layers is large. However, when the touch screen is to be thinned, if the above-mentioned conventional electrode pattern is applied to a touch panel with an ultra-thin structure, the original capacitance value will be too large, and the amount of change will be too small, resulting in a touch screen. Insufficient touch sensitivity and susceptibility to noise interference cause problems such as incorrect touch position determination.

In order to solve the above problems, there is an urgent need in the art for a touch electrode pattern suitable for an ultra-thin touch screen.

The main object of the present invention is to provide a touch electrode pattern, which can form a plurality of hollow regions by reducing the area of each sensing electrode and each driving electrode, and interleaving a plurality of the sensing electrodes and a plurality of the driving electrodes, In order to reduce the mutual capacitance value between the sensing electrode and the driving electrode, and by having two opposite first compensation electrodes and two opposite second compensation electrodes around each of the hollow areas, Each touch point of the touch panel has a uniform initial mutual capacitance value.

In order to achieve the foregoing object, a touch electrode pattern used in a touch display is proposed, which has: a plurality of sensing electrodes provided on a first conductive film, and a plurality of the sensing electrodes are spaced apart from each other. A first compensation electrode; a plurality of driving electrodes provided on a second conductive film, and a plurality of second compensation electrodes provided on the driving electrodes at intervals; and an insulating layer provided on the first conductive film and the first conductive film Between two conductive films; wherein the plurality of sensing electrodes and the plurality of driving electrodes are intersected through the insulating layer to form a plurality of hollow regions, and there are two opposite sides of any one of the hollow regions. The first compensation electrode and two opposite second compensation electrodes.

In a possible embodiment, the first compensation electrode is an electrode selected from the group consisting of a cross-shaped electrode, a diamond-shaped electrode, a m-shaped electrode, and an X-shaped electrode.

In a possible embodiment, the second compensation electrode is an electrode selected from the group consisting of a cross-shaped electrode, a diamond-shaped electrode, a rice-shaped electrode, and an X-shaped electrode.

In a possible embodiment, the first compensation electrode is made of a selected material selected from the group consisting of nano-silver, graphene, and metallic materials.

In a possible embodiment, the second compensation electrode is made of a selected material selected from the group consisting of nano-silver, graphene, and metallic materials.

In one embodiment, the first conductive film is made of indium tin oxide.

In one embodiment, the second conductive film is made of indium tin oxide.

To achieve the foregoing object, the present invention further provides a touch display device, which has a touch screen, and the touch screen has the aforementioned touch electrode pattern.

In order to enable your reviewing committee to further understand the structure, characteristics, and purpose of the present invention, the drawings and detailed description of the preferred embodiments are attached as follows.

Please refer to FIG. 3, which illustrates a schematic diagram of a first embodiment of an electrode pattern arrangement of the present invention. As shown in FIG. 3, a touch pattern includes: a plurality of elongated sensing electrodes 20 spaced apart on a first conductive film, the first conductive film is made of indium tin oxide, and each of the elongated sensing electrodes A plurality of first compensation electrodes 21 are arranged at intervals on 20, wherein the width of the gap between each two adjacent first compensation electrodes 21 can be freely adjusted, and the gap can be added with a dummy block (Dummy block) according to demand; And a plurality of elongated driving electrodes 30 are spaced on the second conductive film, the second conductive film is made of indium tin oxide, and a plurality of second compensations are arranged on each of the elongated driving electrodes 30 at intervals. The electrode 31, wherein the width of the gap between each two adjacent second compensation electrodes 31 can be freely adjusted, and the gap can be added with a virtual filling block according to demand, and the plurality of elongated driving electrodes 30 are connected to the A plurality of elongated sensing electrodes 20 are staggered to form a plurality of hollow regions 40, and an insulating layer 50 is provided between the first conductive film and the second conductive film so that the plurality of elongated sensing electrodes 20 and Said plural The elongated driving electrodes 30 are electrically insulated from each other.

The principle of the present invention is that when the vertical distance between the elongated sensing electrode 20 and the elongated driving electrode 30 is too close, the initial mutual capacitance value can be made due to the reduced electrode area of the elongated sensing electrode 20 and the elongated driving electrode 30. It is reduced, so the change rate of the capacitance value generated by the touch operation can be increased, thereby improving the sensitivity and accuracy of touch sensing. In addition, the cross pattern formed by the first compensation electrode 21 and the elongated sensing electrode 20 and the cross pattern formed by the second compensation electrode 31 and the elongated drive electrode 30 have the effect of increasing the capacitance sensing area, and the first compensation The electrode 21 and the second compensation electrode 31 may be made of a conductive material such as nano-silver, graphene, or metal.

Please refer to FIG. 4, which illustrates a schematic diagram of an application example of the electrode pattern arrangement of the present invention shown in FIG. 3. As shown in FIG. 4, the five elongated sensing electrodes 20 are connected to five receiving ends RX1-RX5, and the five elongated sensing electrodes 30 are connected to five transmitting ends TX1-TX5. Although this application example only has 5 receiving ends RX1-RX5 and 5 transmitting ends TX1-TX5, the present invention is not limited thereto, that is, the electrode pattern of the present invention may have other numbers of elongated sensing electrodes 20 and Other numbers of elongated sensing electrodes 30 provide various touch resolutions.

In FIG. 4, when the touch point is at point A, if the first compensation electrode 21 and the second compensation electrode 31 are not provided, since point A is far away from each of the elongated sensing electrodes (20, 30) around it, RX4 The change in the mutual capacitance value with TX1, TX2 and RX5 and TX1, TX2 will be the smallest; and because point C is located at the intersection of a narrow sensing electrode 20 and a narrow sensing electrode 30, so between RX2 and TX4 The mutual capacitance value will be the largest. In other words, the entire touch panel may have a large difference in capacitance values and unevenness. Therefore, it is important to arrange the first compensation electrode 21 and the second compensation electrode 31 to compensate for the difference in mutual capacitance between different touch points.

Since each of the elongated sensing electrodes 20 and each of the elongated sensing electrodes 30 is provided with a plurality of first compensation electrodes 21 and a plurality of second compensation electrodes 31 arranged at regular intervals, a finger ( (Or stylus, etc.) The touched positions mainly include the three positions A, B, or C. The following uses the finger touch point from C to B and then moves to point A as an example to illustrate the touch detection principle of the present invention:

Point C is directly above the intersection of TX4 and RX2. When the point C is touched, the mutual capacitance values between the plurality of elongated sensing electrodes 20 and the plurality of elongated drive electrodes 30 at the location of the point C are changed, and the mutual capacitance values at the intersection of RX2 and TX4 are changed. The amount of change in the mutual capacitance at the intersection of RX1, RX3 and TX4 and the intersection of RX2 and TX3, TX5 is small. Therefore, a touch drive unit (not shown) can The amount of change to determine the touch position.

When the touch position is moved from point C to point B, as for the elongated sensing electrode 20, the touch point will first approach and then leave the elongated sensing electrode 20 connected to RX3; for the elongated sensing electrode 30, the touch point will Approaches the elongated sensing electrode 30 connected to TX3. During this process, the amount of change in the mutual capacitance at the intersection of RX2 and TX4 will decrease until it is zero.

At point B, there is a large amount of capacitance change at the intersection of RX3 and TX3 and the intersection of RX4 and TX3, and the intersection of RX3 and TX2, the intersection of RX3 and TX4, the intersection of RX4 and TX2, and RX4 There is a small amount of capacitance change at the intersection with TX4. Therefore, the touch driving unit can determine the touch position according to the amount of capacitance change. Specially, because point B is equidistant from RX3 and RX4, the capacitance changes at the intersection of RX3 and TX3 and the intersection of RX4 and TX3 are the same, and the intersection of RX3 and TX2, the intersection of RX3 and TX4, and the intersection of RX4 and At the intersection of TX2 and the intersection of RX4 and TX4, there will be a consistent amount of capacitance change.

When the touch position is moved from point B to point A, as for the elongated sensing electrode 20, the touch point will first approach and then leave the elongated sensing electrode 20 connected to RX4; for the elongated sensing electrode 30, the touch point will Approach and then leave the elongated sensing electrode 30 connected to TX2. In this process, the amount of change in the mutual capacitance at the intersection of RX3 and TX3 and at the intersection of RX4 and TX3 will be reduced to zero.

When point A is reached, the intersection of RX4 and TX1, the intersection of RX4 and TX2, the intersection of RX5 and TX1, and the intersection of RX5 and TX2 will all generate sufficient capacitance changes so that the touch driving unit can To determine the touch position. Specially, when point A is located at the center point of the area defined by TX1, TX2, RX4, and RX5, the intersection of RX4 and TX1, the intersection of RX4 and TX2, the intersection of RX5 and TX1, and the intersection of RX5 and TX2 There will be a consistent change in capacitance everywhere.

In addition, please refer to FIG. 5 to FIG. 7, which are schematic diagrams of electrode pattern arrangement of the second to fourth embodiments of the present invention. As shown in FIG. 5 to FIG. 7, the first compensation electrode 21 and the second compensation electrode 31 of the present invention may be formed by electrode patterns such as X-shaped, m-shaped, or hollow diamond to provide capacitance compensation.

In addition, if the electrode pattern of the present invention is compared with the conventional electrode pattern of the conventional technology, when the sensing thickness is 0.1 mm, the comparison table is shown in Table 2 below:

Table 2 Electrode pattern Initial mutual capacitance value (pF) Capacitance (pF) after placing copper pillar Capacitance change (pF) Proportion of change (%) Known electrode pattern 4.24 3.89 0.35 8.36% Cross-shaped electrode pattern 0.55 0.32 0.23 41.82% X-shaped electrode pattern 0.59 0.34 0.25 42.37% M-shaped electrode pattern 0.62 0.35 0.27 43.55% Diamond electrode pattern 0.64 0.39 0.25 39.06%

As can be seen from Table 2 above, when the compensation electrode of the present invention is compared with a conventional electrode pattern, the various electrode patterns designed by the present invention can greatly reduce the initial mutual capacitance value, and after placing a copper pillar (simulating finger touch), there is a large The value of the capacitance change and the larger change ratio account for the problems of insufficient touch sensitivity and large signal-to-noise ratio in ultra-thin touch panel applications. In addition, it can be seen from Table 2 that the compensation electrodes with different areas will have different effects on the initial mutual capacitance value. Generally, the larger the area of the compensation electrode, the larger the initial mutual capacitance value will be.

In addition, according to the above description, the present invention further provides a touch display device, which has a touch screen, and the touch screen has the aforementioned touch electrode pattern, so that each touch point of the touch screen is uniform. And reduce the initial mutual capacitance value to improve touch sensitivity and signal-to-noise ratio, thereby providing fast and accurate touch performance.

Therefore, with the design disclosed above, the present invention has the following advantages:

1. The technical solution of the present invention can reduce the initial mutual capacitance value by reducing the area of the sensing electrode and the driving electrode.

2. In the technical solution of the present invention, a plurality of first compensation electrodes and a plurality of second compensation electrodes are provided so that each touch point of the touch screen has a uniform initial mutual capacitance value.

3. The technical solution of the present invention can improve touch sensitivity and signal-to-noise ratio to provide fast and accurate touch performance.

What is disclosed in this case is a preferred embodiment. For example, those who have partial changes or modifications that are derived from the technical ideas of this case and are easily inferred by those skilled in the art, do not depart from the scope of patent rights in this case.

To sum up, regardless of the purpose, method and effect, this case is showing its technical characteristics that are quite different from the conventional ones, and its first invention is practical, and it is also in line with the patent requirements of the invention. Granting patents at an early date will benefit society and feel good.

10‧‧‧ Induction electrode

11‧‧‧Drive electrode

12‧‧‧ clearance

13‧‧‧ copper pillar

20‧‧‧Slim and long sensing electrode

21‧‧‧The first compensation electrode

30‧‧‧ Narrow and long driving electrode

31‧‧‧second compensation electrode

40‧‧‧ hollow area

50‧‧‧ Insulation

FIG. 1 is a schematic diagram of a conventional double-layer indium tin oxide electrode pattern. FIG. 2 is a schematic diagram of a simulated touch of a copper pillar of the electrode pattern of the conventional double-layer indium tin oxide in FIG. 1. FIG. 3 is a schematic diagram of a first embodiment of an electrode pattern arrangement of the present invention. FIG. 4 is a schematic diagram of an application example of the electrode pattern arrangement of FIG. 3. FIG. 5 is a schematic diagram of a second embodiment of the electrode pattern arrangement of the present invention. FIG. 6 is a schematic diagram of a third embodiment of the electrode pattern arrangement of the present invention. FIG. 7 is a schematic diagram of a fourth embodiment of the electrode pattern arrangement of the present invention.

Claims (8)

A touch electrode pattern used in a thin touch display has: a plurality of sensing electrodes disposed on a first conductive film, and each of the sensing electrodes is periodically spaced with a first compensation electrode; a plurality of A driving electrode is provided on a second conductive film, and a second compensation electrode is periodically arranged on each of the driving electrodes; and an insulating layer is provided between the first conductive film and the second conductive film; Wherein, the plurality of sensing electrodes and the plurality of driving electrodes are intersected through the insulating layer to form a plurality of hollow regions to reduce the initial mutual capacitance value, and there are two opposite sides of any one of the hollow regions. The first compensation electrode and two opposite second compensation electrodes. The touch electrode pattern according to item 1 of the scope of the patent application, wherein the first compensation electrode is an electrode selected from the group consisting of a cross-shaped electrode, a diamond-shaped electrode, a m-shaped electrode and an X-shaped electrode. According to the touch electrode pattern described in the first item of the patent application scope, wherein the second compensation electrode is an electrode selected from the group consisting of a cross-shaped electrode, a diamond-shaped electrode, a m-shaped electrode, and an X-shaped electrode. The touch electrode pattern according to item 1 of the application, wherein the first compensation electrode is made of a selected material selected from the group consisting of nano-silver, graphene, and metallic materials. The touch electrode pattern according to item 1 of the application, wherein the second compensation electrode is made of a material selected by a group consisting of nano-silver, graphene, and a metal material. The touch electrode pattern according to item 1 of the patent application scope, wherein the first conductive film is made of indium tin oxide. The touch electrode pattern according to item 1 of the patent application scope, wherein the second conductive film is made of indium tin oxide. A thin touch display device has a thin touch screen, and the thin touch screen has a touch electrode pattern according to any one of claims 1-7 of the scope of patent application.