TWI633476B - Touch display device and control method thereof - Google Patents

Abstract

The invention provides a touch display device capable of avoiding horizontal stripes due to high and low temperature and a control method thereof. The touch display device includes a touch display panel, a plurality of data line driving circuits, a plurality of gate line driving circuits, and a driving controller. The touch display panel has a plurality of gate lines, a plurality of data lines, a plurality of touch electrodes, and a plurality of pixels respectively disposed at the intersection of each gate line and each data line; the driving controller controls the plurality of pixels Touching the electrodes to perform a touch operation, and controlling the plurality of gate line driving circuits to sequentially drive the plurality of gate lines according to an input clock, so that the plurality of data line driving circuits write relevant pixel data Corresponding pixels for performing a display operation, the input clock system includes a plurality of clock signals, and the driving controller detects an ambient temperature; when the detected ambient temperature is lower than a preset change, the temperature is lower or higher When a predetermined high temperature changes, the driving controller adjusts the duty cycle of each clock signal of the input clock until a falling edge of one clock signal in the input clock and a rising edge of another clock signal Close to alignment. Thereby, the touch display device of the present invention can effectively avoid display horizontal stripes caused by high and low temperature.

Description

Touch display device and control method thereof

The present invention relates to the technical field of display panels, and more particularly to a touch display device and a method thereof that can avoid horizontal stripes due to high and low temperatures.

In the existing in-cell touch display panel, in order to provide a touch electrode in the display panel to sense the user's finger touch, the common electrode of the original display panel is cut into a plurality of electrodes and double as a touch electrode. In the driving structure of the in-cell touch display panel, the display driving and the touch scanning are generally shared hardware and time sharing, for example, a frame time is display driving and touch. The scan is shared. When the drive data is displayed, the touch scan stops or processes the data, and when the touch scan interval is activated, the display drive stops.

The in-cell touch display panel, as shown in FIG. 1 , is driven by a start pulse signal (STV) to trigger an array gate driver (GOA) to pass through a gate driver circuit G of the gate driver [ i](1...n,n+1,...) is passed down. In the existing design, the gate drive sequence uses the same set of drive signals at any ambient temperature. Generally speaking, the same set of driving signals may display the picture normally at normal temperature, for example, the output waveform of the gate driving circuit G[n], G[n+4] at normal temperature is as shown in Fig. 2(A). It is shown that when the panel is in a high temperature environment (for example, above 50 degrees Celsius), as shown in FIG. 2(B), the falling edge of the output of the gate driving circuit G[n] is delayed backward, and the gate is driven. The rising edge of the output of the circuit G[n+4] will delay the rise, thus causing the disorder of the gate drive timing, or when the panel is in a low temperature environment (for example, below 0 degrees Celsius), as shown in FIG. 2(C). The gate drive circuit G[n], G[n+4] output will not be able to completely transmit the signal due to the low temperature, and the above-mentioned timing disorder or the signal cannot be completely transmitted, the horizontal stripes visible to the human eye can be seen on the screen. In addition, it affects the quality of the display, so it is necessary to improve it.

The object of the present invention is mainly to provide a touch display device and a control method thereof, which can avoid the occurrence of horizontal stripes due to high and low temperature by adjusting the duty ratio of the input clock.

According to a feature of the present invention, a touch display device includes a touch display panel, a plurality of data line driving circuits, a plurality of gate line driving circuits, and a driving controller. The touch display panel has a plurality of a gate electrode line, a plurality of data lines, a plurality of touch electrodes, and a plurality of pixels respectively disposed at each gate line and each data line intersection; the driving controller controls the plurality of touch electrodes to touch Controlling, and controlling the plurality of gate line driving circuits to sequentially drive the plurality of gate lines according to an input clock, so that the plurality of data line driving circuits write relevant pixel data into corresponding pixels for performing Display operation, the input clock system includes a plurality of clock signals, and the driving controller detects an ambient temperature, wherein when the detected ambient temperature is lower than a preset change, the temperature is lower than or higher than a preset When the temperature changes, the driving controller adjusts the duty cycle of each clock signal of the input clock until a falling edge of one clock signal in the input clock and another clock signal Rising edge toward the alignment.

According to another feature of the present invention, the present invention provides a control method for a touch display device, wherein the touch display device includes a touch display panel, a plurality of data line driving circuits, a plurality of gate line driving circuits, and a driving The controller has a plurality of gate lines, a plurality of data lines, a plurality of touch electrodes, and a plurality of pixels respectively disposed at the intersection of each of the gate lines and each of the data lines, and the driving controller controls The touch electrode performs a touch operation, and controls the gate line driving circuit to sequentially drive the gate line according to an input clock including a plurality of clock signals, so that the data line driving circuit writes the relevant pixel data into corresponding Pixel for display operation, the control method comprises: (A) driving the controller to detect the ambient temperature, the touch display device operates with the initial input clock; (B) when the detected ambient temperature is lower than a preset When the temperature changes, the driving controller adjusts the duty cycle of each clock signal of the input clock until the falling edge of one clock signal in the input clock and the other clock signal The rising edge is close to alignment; and (C) when the detected ambient temperature is higher than a predetermined change in temperature, the drive controller adjusts the duty cycle of each clock signal of the input clock until it is input into the clock The falling edge of one clock signal is nearly aligned with the rising edge of another clock signal. Since the present invention can provide a clock signal corresponding to a temperature higher than normal temperature or lower than a normal temperature according to the change of the ambient temperature, the horizontal stripes phenomenon of the display due to high and low temperature can be avoided, and the horizontal stripes phenomenon can be further eliminated on the touch display device. Improve display quality.

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

FIG. 3 is a schematic diagram of the touch display device 30 of the present invention which can avoid horizontal stripes due to high and low temperatures. The touch display device 30 includes a touch display panel 31 , a plurality of data line drive circuits 32 , a plurality of gate line drive circuits 33 , and a drive controller 34 . The touch display panel 31 has a plurality of gate lines 311 , a plurality of data lines 312 , a plurality of pixels 313 , and a plurality of touch electrodes 314 . A pixel 313 is disposed at the intersection of each of the gate lines 311 and each of the data lines 312. Under the control of the driving controller 34, the plurality of gate line driving circuits 33 sequentially drive the plurality of gate lines 311 according to the input clocks CK1 CKCKp (where p is a positive integer), so that the plurality of gate lines 311 are sequentially driven. The data line driving circuit 32 writes the relevant pixel data into the corresponding pixel 313, thereby driving the touch display panel 31 for display.

The plurality of touch electrodes 314 can be cut, for example, by a common common electrode (Vcom), which can serve as a common electrode to provide a common voltage reference during the display interval, and serve as a touch electrode in the touch interval to sense the user. The finger touches and the touch operation is performed accordingly. The plurality of touch electrodes 314 are in different layers from the gate lines 311, the data lines 312, and the pixels 313, and are shown in broken lines in the figure for convenient display. In general, one touch electrode 314 corresponds to a region where a plurality of gate lines 311 and a plurality of data lines 312 intersect. In the example of FIG. 3, one touch electrode 314 corresponds to four gate lines 311 and four. The area where the data line 312 is handed over, but this is only an example for convenience of description. In an actual application, one touch electrode 314 may correspond to an area where eight gate lines 311 and eight data lines 312 are handed over, or twelve. The area where the gate line 311 and the twelve data lines 312 are handed over. That is, one touch electrode 314 can cover a plurality of gate lines 311.

Referring to FIG. 3, when the plurality of gate line driving circuits 33 sequentially drive the plurality of gate lines 311, since the driving signals of the adjacent two gate lines 311 overlap in time, therefore, A coupling capacitor is formed between the gate line 311 and the touch electrode 314. Taking the touch electrode 3141 as an example, the coupling capacitance effect corresponding to the gate lines 3112 and 3113 of the same touch electrode 3141 is uniform, but for two The adjacent touch electrodes 314, such as the touch electrodes 3141 and the touch electrodes 3142 under them, correspond to the coupling capacitance effect formed by the gate lines 3114 of the touch electrodes 3141 and the gates corresponding to the touch electrodes 3142. The coupling capacitance effects formed by the pole lines 3115 are not uniform between each other, which may cause the horizontal stripes on the display of the upper and lower touch electrodes 314.

4 further illustrates the reason why the horizontal stripes appear on the touch display panel 31 and the elimination manner thereof, wherein SX represents a common electrode cut as a touch electrode 3141, and CKn and CKm represent two different in the input clock. The clock signal acts on the gate lines 3114, 3115 corresponding to the two adjacent touch electrodes 3141, 3142, as shown in FIG. 4(A), the falling edge of the pulse signal CKn and the clock signal CKm. The farther the distance of the rising edge is, the brightness of the pixel 313 at the boundary between the upper and lower touch electrodes 314 at this time may cause a difference in the feed through voltage due to the difference in the fall time. To eliminate this difference, the duty ratio of the clock signal of the input clock can be adjusted to an appropriate waveform so that the falling edge of the clock signal CKn is close to the rising edge of the clock signal CKm, as shown in the figure. 4(B), the amplitude of the driving signal coupling of the gate line 311 is reduced in the level of the common electrode SX as a touch electrode 3141, and the driving signal of each gate line 311 is A similar situation can make the picture uniform and solve the horizontal grain problem.

FIG. 5 is an example of eliminating the horizontal stripes by changing the duty ratio of the input clock, wherein the waveform of the original input clock is shown in FIG. 5(A), and the input clock system includes the clock signal. CK1-CK8 has a duty ratio of 43.364%. This input clock is used for the touch display panel to clearly see the horizontal stripes. Therefore, when the duty cycle of each clock signal of the input clock is adjusted to 37.400%. The falling edge of the clock signal CK1 is aligned with the rising edge of the clock signal CK4, so that the waveform of the input clock can eliminate the phenomenon of the horizontal stripes in practical applications.

The invention avoids the occurrence of horizontal stripes on the touch display panel due to high and low temperature by detecting the ambient temperature and by adjusting the duty ratio of the input clock. 6 is a flow chart of a control method of the touch display device capable of avoiding horizontal stripes due to high and low temperature. As shown in the figure, after the power is turned on, the touch display device 30 is at a normal temperature of, for example, 25 degrees Celsius. The operation is performed by the clock signal CK1~CKp of the initial input clock, and the drive controller 34 detects the ambient temperature (step S501); when the detected ambient temperature is lower than a preset change temperature, the drive control The device 34 sets the input clock to a low temperature input clock (step S502), wherein the changing low temperature is, for example, about -10 degrees Celsius, and the low temperature input clock system is each clock signal of the initial input clock. The duty cycle is amplified until the falling edge of one of the clock signals is aligned with the rising edge of the other clock signal, thereby offsetting the difference in the feedthrough voltage to avoid the occurrence of horizontal stripes; at this time, the touch display device The 30 series operates with a low temperature input clock until the ambient temperature detected by the drive controller 34 is above a predetermined low temperature, the drive controller 34 sets the low temperature input clock as the initial input clock ( Step S503), and the touch display device is mounted The reset 30 is operated with the initial input clock and continues to detect the ambient temperature, wherein the low temperature is higher than the low temperature, and the low temperature is, for example, about 0 degrees Celsius.

When the ambient temperature detected by the drive controller 34 is higher than a predetermined change temperature, the drive controller 34 sets the input clock to a high temperature input clock (step S504), wherein the change high temperature is, for example, approximately At 50 degrees Celsius, the high temperature input clock is to reduce the duty cycle of each clock signal of the initial input clock until the falling edge of one of the clock signals is aligned with the rising edge of the other clock signal. To avoid the occurrence of horizontal stripes by offsetting the difference in feedthrough voltage; at this time, the touch display device 30 operates with a high temperature input clock until the ambient temperature detected by the drive controller 34 is lower than a preset When the high temperature is restored, the drive controller 34 sets the high temperature input clock as the initial input clock (step S505), and causes the touch display device 30 to resume operating with the initial input clock, and continues to detect the temperature. Wherein the recovery high temperature is lower than the varying high temperature, and the recovery high temperature is, for example, about 40 degrees Celsius.

7 is a schematic diagram illustrating the use of different input clocks to eliminate horizontal stripes at different ambient temperatures in the foregoing process, which illustrates the present invention in that the detected ambient temperature is below a preset change in low temperature or above a preset. When the temperature changes, the drive controller 34 adjusts the duty cycle of each clock signal of the input clock until the falling edge of one clock signal in the input clock is close to the rising edge of the other clock signal. According to to eliminate the phenomenon of horizontal stripes. That is, when the ambient temperature (for example, 25 degrees Celsius) is input, the clock system is set as the initial input clock, and when the ambient temperature rises to a high temperature (for example, about 50 degrees Celsius), the ambient temperature is too high. The disorder of the gate drive timing causes horizontal stripes on the panel. Therefore, the input clock should be switched to the high temperature input clock to eliminate the horizontal stripes. The touch display device 30 operates at a high temperature input clock until the ambient temperature drops to a high temperature (for example, about 40 degrees Celsius), and the ambient temperature is not too high to cause a horizontal streak on the panel, so the input is input. The clock is switched from the high temperature input clock to the original input clock.

Similarly, when the ambient temperature drops to a low temperature (for example, about -10 degrees Celsius), the input voltage is switched because the ambient temperature is too high and the gate drive signal cannot be completely transmitted and the horizontal stripes appear on the panel. The clock is input at a low temperature to eliminate the horizontal stripes. The touch display device 30 operates at a low temperature input clock until the ambient temperature rises to a low temperature (for example, about 0 degrees Celsius), and the ambient temperature is not too low to cause a horizontal streak on the panel, so the input is input. The clock is switched back to the original input clock by the low temperature input clock.

FIG. 8 is an example of using the high-temperature input clock to eliminate the horizontal stripes phenomenon at a high temperature in the foregoing process, wherein the waveform of the original input clock is shown in FIG. 8(A), and the input clock system includes time. The pulse signal CK1-CK8 has a duty ratio of 49.97%. The input clock can display the panel normally at normal temperature, but at high temperature (higher than the high temperature), the panel will appear horizontal stripes. Therefore, as shown in Figure 8. As shown in (B), the duty cycle of each clock signal of the input clock is reduced to 24.98% by the foregoing procedure, and the falling edge of the clock signal CK1 is aligned with the rising edge of the clock signal CK3. The high temperature input clock, the waveform of the high temperature input clock can eliminate the phenomenon of horizontal stripes in practical applications.

It can be seen from the foregoing description that the present invention can be avoided by using only the sensing temperature circuit inside the driving controller 34 to detect the current ambient temperature, and selecting the currently required input clock, without changing any hardware related equipment. The effect of horizontal stripes on the touch display panel due to high and low temperatures.

In the foregoing examples, the values of the respective temperatures, duty cycles, clocks, and the like are selected for illustrative purposes only and are not intended to limit the scope of the invention. Those skilled in the art can vary the selection of values in accordance with the disclosure of the present invention.

The above-mentioned embodiments are merely examples for convenience of description, and the scope of the claims is intended to be limited to the above embodiments.

30‧‧‧Touch display device
31‧‧‧Touch display panel
32‧‧‧Data line driver circuit
33‧‧‧ gate line drive circuit
34‧‧‧Drive Controller
311‧‧ ‧ gate line
312‧‧‧Information line
313‧‧ ‧ pixels
314‧‧‧Touch electrode
S501-S505‧‧‧Steps

FIG. 1 is a waveform of a driving signal of a conventional in-cell touch display panel. FIG. 2 is a waveform of a driving signal of a conventional in-cell touch display panel at normal temperature, high temperature, and low temperature. FIG. 3 is a schematic view of the touch display device of the present invention which can avoid horizontal stripes due to high and low temperatures. FIG. 4 is a timing diagram for explaining the reason why the horizontal stripes appear on the touch display panel and the elimination manner thereof. Figure 5 shows an example of eliminating the horizontal stripes by adjusting the duty cycle of the input clock. FIG. 6 is a flow chart of a control method of the touch display device according to the present invention which can avoid horizontal stripes due to high and low temperatures. Figure 7 is a schematic diagram illustrating the use of different input clocks to eliminate horizontal stripes at different ambient temperatures. Fig. 8 is a view showing an example of using the high temperature input clock to eliminate the horizontal streak phenomenon at a high temperature in the present invention.

Claims (10)

A touch display device includes: a touch display panel having a plurality of gate lines, a plurality of data lines, a plurality of touch electrodes, and a plurality of gate electrodes and each of the data lines respectively a plurality of data line driving circuits; a plurality of gate line driving circuits; and a driving controller, controlling the plurality of touch electrodes for performing a touch operation, and controlling the plurality of gate line driving circuits to The input clock sequentially drives the plurality of gate lines, so that the plurality of data line driving circuits write relevant pixel data into corresponding pixels for performing a display operation, wherein the input clock system includes a plurality of clock signals, The driving controller detects the ambient temperature; wherein, when the detected ambient temperature is lower than a preset change temperature or higher than a preset change temperature, the drive controller adjusts each of the input clocks The duty cycle of a clock signal until the falling edge of one of the clock pulses in the input clock is nearly aligned with the rising edge of the other clock signal. The touch display device of claim 1, wherein the driving controller sets the input clock to a low temperature input clock when the detected ambient temperature is lower than the change temperature, the low temperature input The clock is obtained by amplifying the duty cycle of each clock of the input clock until the falling edge of one of the clock signals is close to the rising edge of the other clock signal, and when the detected ambient temperature When the temperature is higher than a preset low temperature, the driving controller sets the low temperature input clock as the initial input clock, wherein the change temperature is lower than the return low temperature, and the return low temperature is lower than the normal temperature. The touch display device of claim 2, wherein the change temperature is about 50 degrees Celsius, the change temperature is about -10 degrees Celsius, and the recovery low temperature is about 0 degrees Celsius. The touch display device of claim 1, wherein the driving controller sets the input clock to a high temperature input clock when the detected ambient temperature is higher than the varying temperature, the high temperature input The clock is obtained by reducing the duty cycle of each clock signal of the input clock until the falling edge of one of the clock signals is aligned with the rising edge of the other clock signal, and when the detected ambient temperature When the temperature is lower than a return high temperature, the driving controller sets the high temperature input clock as the initial input clock, wherein the change high temperature is higher than the return high temperature, and the return high temperature is higher than the normal temperature. The touch display device of claim 4, wherein the varying high temperature is about 50 degrees Celsius, the recovery high temperature is about 40 degrees Celsius, and the changing low temperature is about -10 degrees Celsius. A touch display device includes a touch display panel, a plurality of data line driving circuits, a plurality of gate line driving circuits, and a driving controller, wherein the touch display panel has a plurality of gates a plurality of pixels, a plurality of touch electrodes, and a plurality of pixels respectively disposed at the intersection of each of the gate lines and each of the data lines, wherein the driving controller controls the plurality of touch electrodes to perform touch Operating, and controlling the plurality of gate line driving circuits to sequentially drive the plurality of gate lines according to an input clock including a plurality of clock signals, so that the plurality of data line driving circuits write relevant pixel data Corresponding pixels for performing display operations, the control method comprising: (A) the drive controller detects an ambient temperature, the touch display device operates with an initial input clock; (B) when the detected ambient temperature When the temperature is lower than a preset change temperature, the driving controller adjusts the duty ratio of each clock signal of the input clock until a falling edge of a clock signal in the input clock The rising edge of a clock signal is close to alignment; and (C) the drive controller adjusts the duty of each clock signal of the input clock by adjusting the ambient temperature above a predetermined varying temperature The ratio is such that the falling edge of one clock signal in the input clock is nearly aligned with the rising edge of the other clock signal. The control method of claim 6, wherein the step (B) comprises: (B1) when the detected ambient temperature is lower than the change temperature, the drive controller sets the input clock to a low temperature. Inputting a clock, the low temperature input clock is amplified by a duty cycle of each clock signal of the input clock until the falling edge of one of the clock signals is close to the rising edge of the other clock signal; And (B2) when the detected ambient temperature is higher than a predetermined return low temperature, the driving controller sets the low temperature input clock as the initial input clock, wherein the change temperature is lower than the return low temperature The recovery temperature is lower than normal temperature. The control method according to claim 7, wherein the change temperature is about 50 degrees Celsius, the change temperature is about -10 degrees Celsius, and the recovery low temperature is about 0 degrees Celsius. The control method of claim 6, wherein the step (C) comprises: (C1) when the detected ambient temperature is higher than the changed high temperature, the drive controller sets the input clock to a high temperature. Inputting a clock, the high temperature input clock is reduced by a duty cycle of each clock signal of the input clock until a falling edge of one of the clock signals is closely aligned with a rising edge of another clock signal; And (C2) when the detected ambient temperature is lower than a return high temperature, the driving controller sets the high temperature input clock as the initial input clock, the change high temperature is higher than the recovery high temperature, and the recovery high temperature is high At room temperature. The control method according to claim 9, wherein the varying high temperature is about 50 degrees Celsius, the recovery high temperature is about 40 degrees Celsius, and the low temperature is about -10 degrees Celsius.