Embodiments of the present disclosure relate to a touch display panel and a driving method thereof, and a detection method of sensing signals.
Along with continuous development of a display technology, touch screens are applied more and more broadly. According to different working principles, touch screens are generally divided into resistive type touch screens, capacitive type touch screens, infrared type touch screen, etc.
A traditional capacitive touch screen is described as an example; the traditional capacitive touch screen generally comprises touch driving electrodes and touch sensing electrodes. When a drive signal is input to a touch driving electrode, a voltage signal produced by coupling with the touch sensing electrode through a sensing capacitor is correspondingly detected; however, in this process, when a human body touches the capacitive touch screen, an electric field of the human body acts on the sensing capacitor to change the capacitance value of the sensing capacitor, and then a touch position of the human body on the capacitive touch screen can be determined by detecting such change. But all touch driving electrodes in the traditional capacitive touch screen need to be led out to an edge of the touch panel from a touch region of the touch panel, and then led out to outside of the touch panel from the edge of the touch panel and is connected to a control chip. And, the more the touch driving electrodes are lead out, the larger the area of the edge region required by the touch panel is, and thus, the touch device of the traditional capacitive touch screen cannot meet the development trend toward a narrow frame design. Besides, the fact that many touch driving electrodes are lead out causes certain difficulty in binding the touch panel with a flexible circuit panel, and a problem of poor binding easily occurs.
An embodiment of the present disclosure provides a touch display panel, comprising: a plurality of touch driving electrodes and a plurality of touch sensing electrodes provided in a touch region of a touch display panel, and a drive unit provided on an edge of the touch display panel and configured to provide drive signals for the touch display panel; the drive unit includes a first gate drive circuit to an N-th gate drive circuit coupled sequentially in a cascading manner, an enable terminal of the first gate drive circuit is connected to a field sync signal line on the edge of the touch display panel, and an output terminal of a (N−1)-th gate drive circuit is connected to an enable terminal of an adjacent N-th gate drive circuit; an input terminal of the first gate drive circuit to an input terminal of the N-th gate drive circuit are connected to a drive signal line provided on the edge of the touch display panel respectively, and an output terminal of the first gate drive circuit to an output terminal of the N-th gate drive circuit are each correspondingly coupled to one of the touch driving electrodes respectively, where N is an integer greater than or equal to 2.
Another embodiment of the present disclosure provides a driving method for a touch display panel, for driving the above-mentioned touch display panel, comprising: providing, by a drive unit, drive signals for a first gate drive circuit to an N-th gate drive circuit from a drive signal line; providing, by the drive unit, an enable signal for the first gate drive circuit through a field sync signal line, to make the first gate drive circuit charge a touch driving electrode correspondingly coupled to the first gate drive circuit; providing, by the first gate drive circuit, an enable signal for an adjacent second gate drive circuit in a case of N being greater than 2, to make the second gate drive circuit charge a touch driving electrode correspondingly coupled to the second gate drive circuit, and so on, till the (N−1)-th gate drive circuit provides an enable signal for the N-th gate drive circuit, to make the N-th gate drive circuit charge a touch driving electrode correspondingly coupled to the N-th gate drive circuit, thereby finishing a driving process of all touch driving electrodes.
Still another embodiment of the present disclosure provides a detection method of sensing signals, for detecting a sensing signal in the above-mentioned touch display panel and in a case of N being greater than 2, comprising:
step 101: providing, by a drive unit, drive signals for a first gate drive circuit to an N-th gate drive circuit from a drive signal line;
step 102: providing, by the drive unit, an enable signal for the first gate drive circuit through a field sync signal line, to make the first gate drive circuit charge a touch driving electrode correspondingly coupled to the first gate drive circuit; judging whether a first voltage signal coupled from the plurality of touch sensing electrodes is changed, and if yes, determining a node position corresponding to the changed first voltage signal; and
step 103: providing, by the first gate drive circuit, an enable signal for an adjacent second gate drive circuit in a case of N being greater than 2, to make the second gate drive circuit charge a touch driving electrode correspondingly coupled to the second gate drive circuit; judging whether a second voltage signal coupled from the plurality of touch sensing electrodes is changed, and determining a node position corresponding to the changed second voltage signal, and so on, till the (N−1)-th gate drive circuit provides an enable signal for the N-th gate drive circuit, to make the N-th gate drive circuit charge a touch driving electrode correspondingly coupled to the N-th gate drive circuit, judging whether a N-th voltage signal coupled from the plurality of touch sensing electrodes is changed, and if yes, determining a node position corresponding to the changed N-th voltage signal, thereby finishing a detection process of all touch driving electrodes.
In order to clearly illustrate the technical solution of the embodiments of the disclosure, the drawings of the embodiments will be briefly described in the following; it is obvious that the described drawings are only related to some embodiments of the disclosure and thus are not limitative of the disclosure.
In order to make objects, technical details and advantages of the embodiments of the disclosure apparent, the technical solutions of the embodiments will be described in a clearly and fully understandable way in connection with the drawings related to the embodiments of the disclosure. Apparently, the described embodiments are just a part but not all of the embodiments of the disclosure. Based on the described embodiments herein, those skilled in the art can obtain other embodiment(s), without any inventive work, which should be within the scope of the disclosure.
Unless otherwise defined, all the technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which the present disclosure belongs. The terms “first,” “second,” etc., which are used in the description and the claims of the present application for disclosure, are not intended to indicate any sequence, amount or importance, but distinguish various components. Also, the terms such as “a,” “an,” etc., are not intended to limit the amount, but indicate the existence of at least one. The terms “comprise,” “comprising,” “include,” “including,” etc., are intended to specify that the elements or the objects stated before these terms encompass the elements or the objects and equivalents thereof listed after these terms, but do not preclude the other elements or objects. The phrases “connect”, “connected”, etc., are not intended to define a physical connection or mechanical connection, but may include an electrical connection, directly or indirectly. “On,” “under,” “right,” “left” and the like are only used to indicate relative position relationship, and when the position of the object which is described is changed, the relative position relationship may be changed accordingly.
In order to avoid the problem that the touch device cannot meet the development trend toward a narrow frame design and the problem that binding is poor, a traditional capacitive touch screen is modified in the present disclosure. A driving principle similar to a Gate-on-Array (GOA) technology is adopted, shift register units are introduced to both the edge and the touch region of the capacitive touch screen to make the shift register units on the edge serve as drive circuits to input drive signals to the touch driving electrodes in sequence, and to make the shift register units in the touch region scan the nodes corresponding to sensing electrodes. In this way, only drive signal lines connected to the shift register units on the edge need to be led out from the touch region and then connected to a control chip, the development trend of the touch device toward the narrow frame design is met and binding yield is improved. But in the improved capacitive touch screen, because the shift register units are introduced to the edge and the touch region, the capacitive touch screen has problems in a use process for example that scanning periods are long and reporting rate or scanning rate is disadvantageously affected, and when the touch region in such a capacitive touch screen is overlapped with a display region, thin film transistors in the shift register units in the touch region (which is a visible region) are affected by a light-induced degradation effect, and electrical conductivity is reduced. Therefore, a novel touch screen is urgently needed to solve the above problems.
Referring to
As illustrated in the view, the drive unit 110 includes: first (1st) to N-th gate drive circuits GOA-1 to GOA-N coupled sequentially in a cascading manner, an enable terminal of the first gate drive circuit GOA-1 is connected to a field sync signal line CP on the edge of the touch display panel, and an output terminal of a (N−1)-th gate drive circuit GOA-n-1 is connected to an enable terminal of an adjacent (next) N-th gate drive circuit GOA-n; an input terminal of the first gate drive circuit to an input terminal of the N-th gate drive circuit are all connected to a drive signal line CLK provided on the edge of the touch display panel respectively, and an output terminal of the first gate drive circuit to an output terminal of the N-th gate drive circuit are correspondingly coupled to the touch driving electrodes Tx1-Txn respectively, where N (and n) is an integer greater than or equal to 2.
When the drive unit drives the drive touch display panel to operate, the drive signal line provides drive signals for the first through N-th gate drive circuits respectively; the field sync signal line provides an enable signal for the first gate drive circuit, such that the first gate drive circuit begins operating and charges a touch driving electrode correspondingly coupled to the first gate drive circuit according to the received drive signal. When the output terminal of the first gate drive circuit outputs a signal, the output signal provides an enable signal for the adjacent (next) second gate drive circuit while charging the touch driving electrode, such that the second gate drive circuit charges a touch driving electrode correspondingly coupled to the second gate drive circuit, and so on, till the (N−1)-th gate drive circuit provides an enable signal for the N-th gate drive circuit, such that the N-th gate drive circuit charges a touch driving electrode correspondingly coupled to the N-th gate drive circuit, thereby finishing the driving process of the touch display panel by the drive unit.
According to the touch panel of the present embodiment, the drive unit providing the drive signals for the touch display panel is arranged on the edge of the touch display panel and only one drive signal line and one field sync signal line needed for driving, thereby greatly improving binding yield; a wiring design (layout) of a flexible circuit panel bound to the touch display panel becomes simpler accordingly, the package of a control circuit for controlling the touch display panel to work is reduced, and the production cost is reduced.
It should be noted that a specific structure of the touch region of the touch display panel can adopt various structures, for example, a double layer ITO (indium tin oxide) structure or a single layer bridging structure, but the embodiment of the present disclosure is not limited thereto. For the double layer ITO structure, the touch driving electrodes Tx1-Txn and the touch sensing electrodes Rx1-Rxn are made from an ITO material and formed on different layers, and are separated from each other by an insulation layer. For the single layer bridging structure, the touch driving electrodes Tx1-Txn and the touch sensing electrodes Rx1-Rxn are formed in the same layer, for example, each of the touch driving electrodes Tx1-Txn is continuous, while each of the touch sensing electrodes Rx1-Rxn is non-continuous but are segmented by the touch driving electrodes Tx1-Txn, but in the positions intersecting with the touch driving electrodes Tx1-Txn, disconnected electrode segments on both sides of the touch driving electrodes Tx1-Txn are connected by a bridging line on a different layer.
The first to the N-th gate driving electrodes provided by above embodiment are various in configuration as long as the corresponding touch driving electrodes can be driven. For example, the first to the N-th gate drive circuits are shift register circuits. Because the technology of the shift register circuits is relatively mature, the shift register circuits are more stable in a working process, thereby better ensuring implementation of the driving process.
Referring to
Because the thin film transistor in the gate drive circuit may suffer from a current leakage phenomenon due to a photoelectric effect under light illumination, in order to avoid such current leakage, the drive unit can be disposed under a black matrix on the edge of the touch display panel, such that the drive unit is fully covered and shielded by the black matrix. The position of the black matrix is located in the position of the dotted line box as illustrated in
For example, the touch display panel provided by the above embodiment comprises a display panel and a touch panel that are provided separately, and a touch region of the touch display panel is just the touch region of the touch panel, and specific positions of the display panel and the touch panel mainly comprise two examples as follows.
A first positional relationship is that the display panel and the touch panel are two independent parts, and the touch panel is located above the display panel. The touch screen of the touch display panel adopting such structure is, for example, an add-on touch display screen (e.g., OGS, GFF, On-cell structure). In this add-on touch screen, when the drive unit is introduced to the edge of the display panel, a semiconductor layer is needed to be added on the edge of the touch panel as a conducting layer for the thin film transistors in the gate drive circuits of the drive unit, and the material of the semiconductor layer is preferably α-Si. Because α-Si is a kind of direct bandgap semiconductor, its internal structure contains many “suspension bonds”, that is, electrons that do not form bonds with peripheral silicon atoms, and these free electrons can generate current under action of an electric field without aid of phonons. Therefore, the semiconductor layer made of α-Si can be very thin, and the manufacturing cost is relatively low. Other leads in the gate drive circuits can be formed on the same layer as the electrodes (ITO layer or metal layer) with a conductive property in the touch region according to the specific structure of the touch region, that is, the leads and the electrodes with a conductive property in the touch region can be formed at the same time by a one manufacturing process without any additional manufacturing process.
A second positional relationship is that the touch panel is located in the display panel. The touch screen of the touch display panel adopting such structure is an in-cell touch screen (in-cell structure). Such in-cell touch display screen includes a display panel, and the plurality of touch driving electrodes and the plurality of touch sensing electrodes are provided in the display panel, the drive unit for providing drive signals for the touch driving electrodes and the circuits for driving gate lines of the display panel may be synchronously formed on the display panel for example.
For example, the drive unit for providing driving signals for the touch driving electrodes and the circuit for driving the gate line of the display panel are independently arranged without cross noises. During manufacturing, the thin film transistors constituting the drive unit and the thin film transistors constituting the circuits for driving the gate lines of the display panel can be synchronously made without any extra procedure.
Because a GOA technology can be adopted in the display panel, and the gate drive circuits used in the GOA technology are the same as the gate drive circuits in the embodiment of the present disclosure in driving principle, the gate drive circuits for driving the touch panel and the gate drive circuits for driving the display panel can be integrated into the same drive circuits, that is, the drive unit for driving the touch panel and the drive unit for driving the display panel are integrated into the same drive unit, such that the integrated drive unit can drive both the display panel and the touch panel; thus, the operation of manufacturing the drive circuit corresponding to the touch panel does not need to be added, and therefore, the production costs can be reduced and the effects of the narrow frame design and higher binding yield are achieved.
An embodiment of the present disclosure further provides a driving method for a touch display panel, which is used for driving the touch display panel. The driving method for a touch display panel comprises the following steps/operations:
Step S101: providing, by a drive unit, drive signals for a first gate drive circuit to an N-th gate drive circuit from a drive signal line;
Step S102: providing, by the drive unit, an enable signal for the first gate drive circuit through a field sync signal line, to make the first gate drive circuit charge a touch driving electrode correspondingly coupled to the first gate drive circuit;
Step S103: providing, by the first gate drive circuit, an enable signal for an adjacent second gate drive circuit in a case of N being greater than 2, to make the second gate drive circuit charge a touch driving electrode correspondingly coupled to the second gate drive circuit, and so on, till the (N−1)-th gate drive circuit provides an enable signal for the N-th gate drive circuit, to make the N-th gate drive circuit charge a touch driving electrode correspondingly coupled to the N-th gate drive circuit, thereby finishing a driving process of all touch driving electrodes.
Referring to
The driving method in the present embodiment is suitable for the touch display panel, the edge of which is provided with the drive unit, only a drive signal and a field sync signal need to be provided for the drive unit in the driving operation, and the binding yield is improved; a wiring design (layout) of a flexible circuit panel bound to the touch display panel becomes simpler accordingly, the package of a control circuit for controlling the touch display panel to work is reduced, and the production costs are reduced.
An embodiment of the present disclosure further provides a detection method of sensing signals, for detecting a sensing signal in the above touch display panel and in a case where N is larger than 2, the detection method of sensing signals comprises the following steps:
Step 101: providing, by a drive unit, drive signals for a first to a N-th gate drive circuits from a drive signal line;
Step 102: providing, by the drive unit, an enable signal for the first gate drive circuit through a field sync signal line, to make the first gate drive circuit charge a touch driving electrode correspondingly coupled to the first gate drive circuit; judging whether a first voltage signal coupled from the plurality of touch sensing electrodes is changed, and if yes, determining a node position corresponding to the changed first voltage signal;
Step 103: providing, by the first gate drive circuit, an enable signal for an adjacent second gate drive circuit in a case of N being greater than 2, to make the second gate drive circuit charge a touch driving electrode correspondingly coupled to the second gate drive circuit; judging whether a second voltage signal coupled from the plurality of touch sensing electrodes is changed, and determining a node position corresponding to the changed second voltage signal, and so on, till the (N−1)-th gate drive circuit provides an enable signal for the N-th gate drive circuit, to make the N-th gate drive circuit charge a touch driving electrode correspondingly coupled to the N-th gate drive circuit, judging whether a N-th voltage signal coupled from the plurality of touch sensing electrodes is changed, and if yes, determining a node position corresponding to the changed N-th voltage signal, thereby finishing a detection process of all touch driving electrodes.
It is noted that when all touch driving electrodes in the touch display panel are subjected to detection of the sensing signals for many times, steps 101-103 can be executed circularly.
In addition, in the above circulation process, when the touch driving electrode Txn correspondingly coupled to the N-th gate drive circuit has been charged, but the detection process has not come to an end yet, a next charging process might have begun, and thus the charging process and the detection process are not synchronized well; for example, in order to avoid such phenomenon, every time after step 103 is executed, a blank time period is inserted, and till the processing on the data required in detection at the present scanning circle is finished, the step 101 in a next cycle is executed.
In practice, every time after the scanning of the touch driving electrodes is finished and before the enable signal for the next frame reaches, a plurality of CLK periods are added to achieve a synchronizing function. The number of the CLK periods that need to be specifically added may be the time for data processing in the touch detection in this circle (i.e., the scanning of the touch electrodes in the present circle), and is specifically related to the processing speed of a Microcontroller Unit (MCU) for processing the touch detection data. This treatment is equivalent to addition of a plurality of virtual touch driving electrodes in the touch panel, after the operation of the step 103 is finished and before the operation of the step 101 is executed again, the plurality of touch driving electrodes are subjected to the detection of the sensing signal.
In the description of the above embodiments, the specific features, structures, materials or characteristics can be combined in a proper way in any one or more embodiments or examples.
The foregoing embodiments merely are exemplary embodiments of the disclosure, and not intended to define the scope of the disclosure, and the scope of the disclosure is determined by the appended claims.
The application claims priority of Chinese Patent Application No. 201610090061.0 filed on Feb. 17, 2016, the disclosure of which is incorporated herein by reference in its entirety as part of the present application.
Number | Date | Country | Kind |
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201610090061.0 | Feb 2016 | CN | national |