Touch control substrate, touch control display panel and touch control display device

Abstract

The present invention provides a touch control substrate, a touch control display panel, and a touch control display device. The touch control substrate includes: a substrate; a plurality of touch control units distributed in an array on the same layer of the substrate, each touch control unit including at least one first electrode and at least one second electrode, the second electrodes being arranged between adjacent first electrodes, and the maximum working contact size of the touch control substrate not being equal to the diameter of the smallest circle covering all the second electrodes in the touch control unit. According to the touch control substrate of the embodiment of the present invention, by making the maximum working contact size of the touch control substrate not equal to the diameter of the smallest circle covering all the second electrodes in a touch control unit, the phenomenon that the self-capacitance array of the second electrodes in the touch control unit is zero when measuring the self-capacitance of the second electrodes in a differential manner can be avoided, thereby solving the problem that touch detection cannot be performed in a humid environment or under weak grounding conditions.

Description

Technical Field

[0001] The present invention relates to the field of touch technology, and particularly to a touch substrate, a touch display panel, and a touch display device. Background Art

[0002] Currently, with the emergence of high-definition organic light-emitting display technology, combined with the use of high-capacitance loads, thinner or foldable materials, the adverse effects of display noise have become more obvious. Therefore, the performance of touch sensors may be affected by low signal-to-noise ratio (SNR) and loss of touch sensitivity. One solution to these performance problems is to use differential sensing measurement as a method to reduce noise while solving the sensitivity problem of high-capacitive loads. In self-capacitance measurement, the working principle of differential sensing measurement is to distinguish the capacitive loads between the driving electrode and the sensing electrode so as to only emphasize the difference between their capacitive loads. However, when using differential sensing measurement, it may cause the touch sensor to be unable to perform touch detection in a humid environment or under weak grounding conditions. Summary of the Invention

[0003] In view of this, the present invention provides a touch substrate, a touch display panel, and a touch display device, which can solve the problem that when differential sensing measurement is used in the prior art, the touch sensor may be unable to perform touch detection in a humid environment or under weak grounding conditions.

[0004] To solve the above technical problems, the present invention adopts the following technical solutions:

[0005] An embodiment of the first aspect of the present invention provides a touch substrate, which includes:

[0006] A substrate;

[0007] A plurality of touch units distributed in an array on the same layer of the substrate, each touch unit includes at least one first electrode and at least one second electrode, the second electrodes are arranged between adjacent first electrodes, and the maximum working contact size of the touch substrate is not equal to the diameter of the smallest circle covering all the second electrodes in the touch unit.

[0008] Optionally, the arrangement of the first electrode and the second electrode satisfies the following conditions:

[0009]

[0010] Wherein, TD Max is the maximum working contact size of the touch substrate, Num RX is the number of second electrodes in the touch unit, PitchXX is the distance between adjacent first electrodes, PitchYY is the distance between adjacent second electrodes, and π is the constant of the circumference ratio.

[0011] Optionally, the first electrodes of multiple touch units located in the same row are arranged at intervals in the row direction.

[0012] Optionally, at least two second electrodes are included between two adjacent first electrodes, and the at least two second electrodes between two adjacent first electrodes are arranged at intervals in the column direction.

[0013] Optionally, within the same touch unit, the length of the first electrode in the column direction is the same as or approximately the same as the length of the area occupied by the at least two second electrodes located between two adjacent first electrodes in the column direction.

[0014] Optionally, the number of second electrodes between every two adjacent first electrodes is equal.

[0015] Optionally, the number of the second electrodes arranged between every two adjacent first electrodes is 3 or 4.

[0016] Optionally, the first electrode is a driving electrode, and the second electrode is a sensing electrode.

[0017] An embodiment of the second aspect of the present invention further provides a touch display panel, and the touch display panel includes the touch substrate as described in the embodiment of the first aspect.

[0018] An embodiment of the third aspect of the present invention further provides a touch display device, and the touch display device includes the touch display panel as described in the embodiment of the second aspect.

[0019] The beneficial effects of the above technical solutions of the present invention are as follows:

[0020] According to the touch substrate of the embodiment of the present invention, by making the maximum working contact size of the touch substrate not equal to the diameter of the smallest circle covering all the second electrodes in one touch unit, the phenomenon that the self-capacitance array of the second electrodes in the touch unit is zero when measuring the self-capacitance of the second electrodes in a differential manner can be avoided, thereby solving the problem that touch detection cannot be performed in a humid environment or a weak grounding situation. Description of the Drawings

[0021] Figure 1 Schematic diagram of a node in a single-layer touch in the prior art;

[0022] Figure 2 Schematic diagram of the structure of a touch substrate provided by an embodiment of the present invention. Detailed Embodiments

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention fall within the scope of protection of the present invention.

[0024] Please refer to Figure 1 , which is a schematic diagram of a node in a single-layer touch in the prior art. As Figure 1 shown, in a discontinuous single-layer touch design, a common touch unit includes a driving electrode T1 and three sensing electrodes (R1 to R3). That is to say, within one touch unit, one driving electrode corresponds to three sensing electrodes, and a node 11 is formed between the driving electrode and one sensing electrode.

[0025] In the prior art, to reduce the impact of low signal-to-noise ratio and touch sensitivity loss on the performance of a touch sensor, a common solution is to use differential sensing measurement as a method to reduce noise and at the same time solve the problem of high capacitive load sensitivity. In self-capacitance measurement, the working principle of differential sensing measurement is to distinguish the capacitive load between the driving electrode and the sensing electrode so as to only emphasize the difference between their capacitive loads. The advantage of this technology is that it only deals with the residual capacitive load between electrodes instead of preventing their self-capacitance.

[0026] However, if the touch size accurately and proportionally covers all the sensing electrodes within the touch unit, when applying the differential self-capacitance measurement method to the sensing electrodes, the self-capacitance array will be zero because they will be exposed to the accurate charge transfer amount of the touch. Therefore, in this case, self-capacitance-related applications cannot be used, such as moisture detection or low ground mass (LGM) touch reconstruction, etc. This effect is called "the large touch self-capacitance cancellation effect".

[0027] Therefore, please refer to Figure 2 , which is a schematic structural diagram of a touch substrate provided by an embodiment of the present invention. As Figure 2 shown, the touch substrate provided by the embodiment of the present invention may include: a substrate; a plurality of touch units located on the same layer of the substrate, and the plurality of touch units may be arranged in an array on one side of the substrate. Wherein, each touch unit includes at least one first electrode and at least one second electrode, and the first electrode and the second electrode may be configured asymmetrically. The asymmetric configuration is as Figure 1As shown, in the touch unit, the first electrode and the second electrode may have a minimum repeating unit, which can be represented by mTnR. Here, m represents the number of the first electrodes, and n represents the number of the second electrodes. Moreover, the second electrodes are arranged between adjacent first electrodes. For example, in the case where each touch unit includes only one first electrode, the second electrodes are arranged between two adjacent first electrodes in two adjacent touch units. And in the case where each touch unit includes at least two first electrodes, the second electrodes are arranged between two adjacent first electrodes in the same touch unit. In some alternative embodiments, the second electrodes may also be arranged between two adjacent first electrodes in two adjacent touch units. Further, the maximum working contact size of the touch substrate is not equal to the diameter of the smallest circle covering all the second electrodes in the touch unit. Any manufacturer will specify the maximum and minimum working contact sizes when meeting specific performance criteria during the production of touch sensors. Therefore, the maximum working contact size of the touch substrate can be a preset value. When considering the circular contact size, there is a smallest circle that can cover all the second electrodes in any touch unit. By making the maximum working contact size of the touch substrate not equal to the diameter of this smallest circle, it can be avoided that when the contact size between the touch object and the touch substrate during the touch process is exactly equal to the maximum working contact size of the touch substrate, all the second electrodes in a touch unit are just covered, thereby avoiding the phenomenon that the self-capacitance array is zero when using the differential self-capacitance measurement method for the second electrodes in the touch unit. Thus, when the touch substrate uses the differential self-capacitance measurement, it can still perform touch applications such as humidity detection or weak-ground touch reconstruction. Here, the second electrodes are sensing electrodes.

[0028] In an embodiment of the present invention, optionally, in a touch unit, the number of the minimum repeating units is the same as the number of the second electrodes in the minimum repeating unit.

[0029] As Figure 2 shown, in the electrode arrangement design of this touch substrate, a touch unit 21 can be composed of 4 driving electrodes TX0 and 16 sensing electrodes (RX0 to RX15). In this touch unit 21, the smallest repeating unit is a driving electrode and the corresponding 4 sensing electrodes. At this time, this smallest repeating unit can be called a 1T4R touch sensor. It can be known that the smallest repeating unit in the embodiment of the present invention can be mTnR, that is, m driving electrodes and the corresponding n sensing electrodes, where m and n are both positive integers, and the minimum value can be 1.

[0030] In some embodiments of the present invention, optionally, the first electrodes of multiple touch units in the same row are arranged at intervals in the row direction. That is to say, in the case where only one first electrode is included in a touch unit, the first electrodes in multiple touch units in the same row are arranged at intervals in the row direction. And in the case where at least two first electrodes are included in a touch unit, the first electrodes in the same touch unit are all arranged at intervals in the row direction. Thus, the first electrodes in different touch units will also be arranged at intervals in the row direction.

[0031] In some other embodiments of the present invention, optionally, in the case where a touch unit only includes one second electrode, since multiple touch units located on the substrate are arranged in an array, each second electrode will be located between two adjacent first electrodes in two adjacent touch units. And in the case where a touch unit includes multiple second electrodes, at least two second electrodes are included between two adjacent first electrodes, and the at least two second electrodes between two adjacent first electrodes are arranged at intervals in the column direction. That is to say, at least two second electrodes can be included between every two adjacent first electrodes, and the at least two second electrodes arranged between two adjacent first electrodes are arranged at intervals in the column direction, where the column direction is perpendicular to the row direction. Thus, in the same touch unit, each first electrode corresponds to at least two second electrodes, that is, an asymmetric electrode configuration method is adopted, which can reduce the touch failure area caused by the wiring distribution of the first electrode and the second electrode in the touch area, and can also meet the requirements of electrode signal processing at both the head and tail ends.

[0032] In an embodiment of the present invention, optionally, within the same touch unit, the length of the first electrode in the column direction is the same as or approximately the same as the length of the area occupied by at least two second electrodes between two adjacent first electrodes in the column direction. That is to say, the length of the area occupied by at least two second electrodes between two adjacent first electrodes in the column direction can be equal to the length of the first electrode in the column direction, or slightly less than the length of the first electrode in the column direction, so as to avoid the problem that the second electrode protrudes in the column direction and makes the touch units in the column direction inconvenient to arrange, and being approximately the same can also ensure that the first electrode and the second electrode effectively cover the touch area and improve the touch sensitivity.

[0033] In an embodiment of the present invention, optionally, the number of second electrodes between every two adjacent first electrodes is equal to ensure consistent touch sensitivity. In an alternative embodiment, in the touch unit, the number of second electrodes arranged between every two adjacent first electrodes is 3, that is, one first electrode corresponds to 3 second electrodes, and the minimum repeating unit is 1T3R; in another alternative embodiment, in the touch unit, the number of second electrodes arranged between every two adjacent first electrodes is 4, that is, one first electrode corresponds to 4 second electrodes, and the minimum repeating unit is 1T4R. Of course, it can be understood that under the concept of the present invention, one first electrode can also correspond to 2 second electrodes, 5 second electrodes, 6 second electrodes, etc., and the present invention does not make specific limitations.

[0034] In an embodiment of the present invention, the first electrode can be a driving electrode, and the second electrode is an induction electrode.

[0035] In an embodiment of the present invention, to make the maximum working contact size of the touch substrate not equal to the diameter of the smallest circle covering all the second electrodes in the touch unit, the arrangement of the first electrode and the second electrode satisfies the following conditions:

[0036]

[0037] where TD Max is the maximum working contact size of the touch substrate, Num RX is the number of second electrodes in the touch unit, PitchXX is the pitch between two adjacent first electrodes, PitchYY is the pitch between two adjacent second electrodes, and π is the constant of the circumference ratio.

[0038] It should be noted that PitchXX, the pitch between two adjacent first electrodes, can refer to the distance between the centers of two adjacent first electrodes in the same row, or the distance between the sides of two adjacent first electrodes in the same row.

[0039] The derivation process of the above formula is introduced below.

[0040] Taking a touch sensor (minimum repeating unit) with a minimum repeating unit of mTnR as an example, that is, m first electrodes (driving electrodes) and n second electrodes (induction electrodes), the area of the square touch size required to cover all the second electrodes is:

[0041]

[0042] That is:

[0043] Num RX ·PitchXX·PitchYY;

[0044] Among them, PitchXX is the pitch between two adjacent first electrodes, PitchYY is the pitch between two adjacent second electrodes, and Num RX is the number of second electrodes in the touch unit.

[0045] In practical applications, only circular contacts can be considered. That is, the area of the smallest circular touch size required to cover all second electrodes can be assumed to be:

[0046]

[0047] Among them, D is the diameter of the smallest circle. Then, by making:

[0048]

[0049] Solving gives:

[0050]

[0051] Therefore, let TD Max be the maximum working contact size of the touch substrate. As long as it satisfies:

[0052]

[0053] That is to say, at least the maximum working contact size of the touch substrate is not equal to the diameter of the smallest circle required to cover all second electrodes. Thus, it can be ensured that during the differential sensing measurement process, even if the contact size of the touch object with the touch substrate just covers all second electrodes in a touch unit, since the maximum working contact size of the touch substrate is not equal to the contact size of the touch object with the touch substrate, the self-capacitance array of the second electrodes will not be zero, so that the touch substrate can still perform touch applications such as humidity detection or weak-ground touch reconstruction.

[0054] For the touch substrate according to the embodiment of the present invention, by making the maximum working contact size of the touch substrate not equal to the diameter of the smallest circle covering all second electrodes in a touch unit, the phenomenon that the self-capacitance array of the second electrodes in the touch unit becomes zero when measuring the self-capacitance of the second electrodes by the differential method can be avoided, thereby solving the problem of inability to perform touch detection in a humid environment or under weak grounding.

[0055] Another embodiment of the present invention further provides a touch display panel, which includes the touch control substrate described in the above embodiment. A display module is further disposed between the substrate and the touch control unit to achieve the touch display function. Since in the touch control substrate in the above embodiment, according to the touch control substrate of the embodiment of the present invention, by making the maximum working contact size of the touch control substrate not equal to the diameter of the smallest circle covering all the second electrodes in a touch control unit, the phenomenon that the self-capacitance array of the second electrodes in the touch control unit is zero when measuring the self-capacitance of the second electrodes in a differential manner can be avoided, thereby solving the problem that touch detection cannot be performed in a humid environment or a weak grounding situation. The touch display panel in this embodiment also correspondingly has the above beneficial effects. To avoid repetition, it will not be elaborated here.

[0056] Another embodiment of the present invention further provides a touch display device, which includes the touch display panel described in the above embodiment. The touch display device also has the beneficial effects of the above touch display panel. To avoid repetition, it will not be elaborated here.

[0057] The above are some embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A touch substrate, characterized in that, Comprising: A substrate; A plurality of touch units arranged in an array on the same layer of the substrate, each touch unit including at least one first electrode and at least one second electrode, the second electrodes being arranged between adjacent first electrodes, and the maximum working contact size of the touch substrate not being equal to the diameter of the smallest circle covering all the second electrodes in the touch units; The arrangement of the first electrode and the second electrode satisfies the following conditions: Among them, TD Max is the maximum working contact size of the touch substrate, Num RX is the number of the second electrodes in the touch unit, PitchXX is the pitch between two adjacent first electrodes, PitchYY is the pitch between two adjacent second electrodes, and π is the constant of the circumference ratio; The first electrodes of a plurality of touch units in the same row are arranged at intervals in the row direction.

2. The touch control substrate according to claim 1, wherein There are at least two second electrodes between two adjacent first electrodes, and the at least two second electrodes between two adjacent first electrodes are arranged at intervals in the column direction.

3. The touch control substrate according to claim 1, wherein Within the same touch unit, the length of the first electrode in the column direction is the same as or substantially the same as the length of the area occupied by at least two second electrodes between two adjacent first electrodes in the column direction.

4. The touch control substrate according to claim 1, wherein The number of second electrodes between every two adjacent first electrodes is equal.

5. The touch control substrate according to claim 1, wherein The number of the second electrodes arranged between every two adjacent first electrodes is 3 or 4.

6. The touch control substrate according to claim 1, wherein The first electrode is a driving electrode, and the second electrode is a sensing electrode.

7. A touch display panel, characterized in that, Comprising a touch substrate according to any one of claims 1-6.

8. A touch display device, characterized in that, Comprising a touch display panel according to claim 7.

Images