In-cell touch display panel

An in-cell touch display panel includes an active device array substrate, an opposite substrate and a display medium layer. The active device array substrate includes a substrate, a plurality of active devices, a plurality of pixel electrodes, a plurality of common electrodes, a plurality of data signal lines and a plurality of switches. The pixel electrodes are respectively electrically connected to the corresponding active devices. The common electrodes are arranged into a plurality of common electrode series, wherein every two or more common electrode series are connected to each other to form a first touch electrode. The data signal lines are respectively coupled to the pixel electrodes through the corresponding active devices. Every two or more of the data signal lines are electrically connected to one of the switches, wherein the pixel electrodes and the data signal lines coupled to a same switch together form a second touch electrode.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Taiwan application serial no. 102125588, filed on Jul. 17, 2013. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention generally relates to a display panel, and more particularly, to an in-cell touch display panel.

2. Description of Related Art

A touch panel can be roughly divided into an on-cell touch display panel, an integrated touch display panel and an in-cell touch display panel according to the disposing layout of the touch panel and the display panel. For the on-cell touch display panel, the touch components are usually fabricated on a substrate to form a touch panel, followed by adhering the touch panel onto the outer surface of the display panel. For the integrated touch display panel, the touch components are integrated onto the display panel. For the in-cell touch display panel, the touch components are directly integrated inside the display panel. Compared to the on-cell touch display panel, the integrated touch display panel and the in-cell touch display panel are quite suitable for thinning and lightening a display.

Regardless the on-cell touch display panel, the integrated touch display panel or the in-cell touch display panel, in order to form a touch display panel, it must additionally conduct several photomask processes under the original touch panel architecture to finish the fabrication of the touch components, i.e., a touch display panel requires considerable processes to be finished.

SUMMARY OF THE INVENTION

Accordingly, the invention is directed to an in-cell touch display panel configured to integrate touch components into the fabrication of a display panel and to achieve touching and displaying functions through time division driving.

An in-cell touch display panel of the invention includes an active device array substrate, an opposite substrate and a display medium layer. The active device array substrate includes a substrate, a plurality of active devices, a plurality of pixel electrodes, a plurality of common electrodes, a plurality of data signal lines and a plurality of switches. The substrate has a display region and a peripheral region adjacent to the display region. The active devices are arranged in an array in the display region. The pixel electrodes are located in the display region and respectively electrically connected to the corresponding active devices. The common electrodes are located in the display region and are respectively corresponding to the pixel electrodes, in which the common electrodes are arranged into a plurality of common electrode series and each of the common electrode series extends along a first direction, in which every two or more common electrode series are connected to each other to form a first touch electrode so that all the common electrodes of the active device array substrate form a plurality of first touch electrodes sequentially arranged along a second direction. The data signal lines are located in the display region and respectively coupled to the pixel electrodes through the corresponding active devices. Every two or more of the data signal lines are electrically connected to one of the switches, the pixel electrodes and the data signal lines coupled to a same switch together form a second touch electrode to make all the data signal lines and all the pixel electrodes of the active device array substrate folin a plurality of second touch electrodes arranged along the first direction. The opposite substrate is opposite to the active device array substrate. The display medium layer is disposed between the active device array substrate and the opposite substrate.

A method of driving the in-cell touch display panel of the invention includes following steps: first, independently driving each of the data signal lines in a display cycle; next, sequentially driving the second touch electrodes in a touching cycle, in which when each of the second touch electrodes is driven, all the data signal lines corresponding to each of the second touch electrodes are simultaneously driven, wherein the display cycle and the touching cycle are not overlapped with each other.

Based on the description above, when the in-cell touch display panel of the invention is in the display cycle, each of the data signal lines is independently enabled so that the common electrodes and the pixel electrodes drive the display medium layer to realize the general displaying function; in the touching cycle, the data signal lines connected to the same switch are simultaneously enabled so that the pixel electrodes and the data signal lines connected to the same switch together form the first touch electrode. In other words, the pixel electrodes can realize the touching function through the designs of the data signal lines and the switches.

In order to make the features and advantages of the present invention more comprehensible, the present invention is further described in detail in the following with reference to the embodiments and the accompanying drawings.

DESCRIPTION OF THE EMBODIMENTS

FIG. 1is a cross-sectional diagram of an in-cell touch display panel according to an embodiment of the invention. Referring toFIG. 1, an in-cell touch display panel10of the invention includes an active device array substrate100, an opposite substrate200and a display medium layer300. The opposite substrate200is opposite to the active device array substrate100and the display medium layer300is disposed between the active device array substrate100and the opposite substrate200. In the embodiment, the opposite substrate200is, for example, a color filter substrate having a color filter layer and a black matrix layer. The display medium layer300is, for example, a liquid crystal molecules layer, which the invention is not limited to.

FIG. 2is a top-view diagram of an active device array substrate according to an embodiment of the invention andFIGS. 3A-3Eare schematic layout diagram of all the parts inFIG. 2.FIG. 1is a cross-sectional view of the active device array substrate100along a section line A-A′ depicted inFIG. 1. Referring toFIGS. 1,2and3A-3E. The active device array substrate100includes a substrate102, a plurality of data signal lines110and a plurality of scan lines120. The substrate102has a display region102aand a peripheral region102badjacent to the display region102a(as shown inFIG. 5). Each of the scan lines120is disposed on the substrate102and extends along a first direction D1, and each of the data signal lines110is disposed on the substrate102and extends along a second direction D2. In the embodiment, preferably, the first direction D1is perpendicular to the second direction D2, which the invention is not limited to.

The scan lines120and the data signal lines110are disposed alternately so as to define a plurality of sub-pixel regions arranged in an array in the display region102aof the substrate102. Each of the sub-pixel regions has a sub-pixel unit therein. In more details, the sub-pixel unit includes an active device130, a pixel electrode140and a common electrode150. The active device130is electrically connected to one of the scan lines120and one of the data signal lines110. The pixel electrode140is, for example, electrically connected to one of the active devices130. The common electrode150is disposed over the pixel electrode140and insulated from the pixel electrode140.

The active device130includes a gate132, a channel layer134, a source136and a drain138. The active devices130are arranged in the display region102ain the array. The gate132is disposed on the substrate102. A gate insulation layer133covers the gate132and the substrate102. The channel layer134is disposed on the gate insulation layer133over the gate132. The source136and the drain138are separated from each other and respectively cover partial areas of the channel layer134. The active device130is connected to the data signal line110through the source136and is connected to the scan line120through the gate132. The active device130in the embodiment is, for example, a bottom gate type thin film transistor; in other embodiments, the active device130can be a top gate type thin film transistor, which the invention is not limited to.

The pixel electrode140is electrically connected to the drain138of the active device130. Specifically, the pixel electrode140can be fabricated on the gate insulation layer133, followed by fabricating the drain138and making the drain138cover the pixel electrode140. In other words, the drain138can directly contact the pixel electrode140to make them electrically connected to each other. When the active device130is turn on, the signal of the data signal line110can be transmitted to the pixel electrode140through the active device130so as to drive the pixel electrode140. The pixel electrodes140in the same column arranged along the second direction D2are coupled to the same data signal line110so that the pixel electrodes140in the same column are driven by the same data signal line110. Each of the data signal lines110extends to the peripheral region102bfrom the display region102aand electrically connected to a switch160.

FIG. 4is a top-view diagram of the common electrodes according to an embodiment of the invention. Referring toFIGS. 1,2and4, in every sub-pixel unit, a common electrode150and a pixel electrode140are correspondingly disposed. An insulation layer145is disposed between the common electrode150and the pixel electrode140to make them insulated from each other, as shown inFIG. 1. In the embodiment, the pixel electrode140is fabricated, followed by fabricating the common electrode150, so that the common electrode150is located above the pixel electrode140, in which the pixel electrodes140at the lower position has a continuous pattern without slit, while the common electrodes150has a pattern with multiple slits. Since the pixel electrodes140and the common electrodes150are disposed on the same substrate and located at the same side of the display medium layer300, a lateral electrical field can be formed between the common electrodes150and the pixel electrodes140to drive the display medium in the display medium layer300.

In other embodiments, it can be upside down that the common electrode150is fabricated first, followed by fabricating the pixel electrode140so as to form the pixel electrode140located above the common electrode150. At the time, the common electrodes150at the upper position have a continuous pattern without slit, while the pixel electrodes140have a pattern with multiple slits. In the same way, since the pixel electrodes140and the common electrodes150are disposed on the same substrate and located at the same side of the display medium layer300, a lateral electrical field can be formed between the common electrodes150and the pixel electrodes140to drive the display medium in the display medium layer300.

As shown byFIG. 4, the common electrodes150are arranged to form a plurality of common electrode series150S, and the common electrode series150S are arranged along the second direction D2, wherein each of the common electrode series150S extends along the first direction D1. Moreover, every two or more common electrode series150S are connected together to form a first touch electrode E1, and the first touch electrodes E1are separated from each other by a gap G. The first touch electrodes El are arranged along the second direction D2, and each of first touch electrodes E1extends along the first direction D1. In short, all the common electrodes150of the embodiment form the plurality of the first touch electrodes E1.

FIG. 5is a top-view diagram of an active device array substrate according to an embodiment of the invention.FIG. 5only schematically illustrates the layout of the pixel electrodes140and the common electrodes150, not showing the details of the part shapes and the disposing thereof. A partial area P inFIG. 5can refer the partial area P ofFIG. 2, whereinFIG. 2has more details to show the part shapes and the disposing thereof.

Referring toFIG. 5, the plurality of first touch electrodes E1are disposed in the display region102aof the substrate102, while the plurality of common signal lines170are disposed in the peripheral region102bto be electrically connected to the corresponding first touch electrodes E1respectively. The common signal lines170transmit the signals to the corresponding first touch electrodes E1.

In the embodiment, several adjacent data signal lines110are electrically connected to the same switch160. At the time, the data signal lines110and the pixel electrodes140coupled to the data signal lines110form one of second touch electrodes E2electrically connected to the same switch160. Thus, the pixel electrodes140and the data signal lines110of the embodiment form the plurality of second touch electrodes E2arranged along the first direction D1, and each of the second touch electrodes E2extends along the second direction D2. In the embodiment, as an example, five adjacent data signal lines110are electrically connected to the same switch160, which the invention is not limited to. People skilled in the art can adjust the number of the data signal lines110connected to the same switch160according to the design requirement.

The switch160is, for example, a thin film transistor or a circuit designed to have function of switching circuit. The switch160can be disposed in the peripheral region102bof the substrate102or can be integrated into the fabrication of a driving chip, wherein the driving chip can be bonded on the substrate102or the driving chip can be electrically connected to the data signal lines110through a flexible printed circuit board. In other words, the invention does not limit the actual disposing position of the switch160. Once the data signal lines110can be electrically connected to the corresponding switches160, it can realize the design of the invention.

As shown byFIG. 5, the active device array substrate100includes a plurality of first touch electrodes E1composed of the common electrodes150and a plurality of second touch electrodes E2composed of the pixel electrodes140and the data signal lines110. The first touch electrodes E1extend along the first direction D1and the second touch electrodes E2extend along the second direction D2. The first touch electrodes E1and the second touch electrodes E2are alternately disposed and form a plurality of sensing areas S. In an embodiment, for each of the first touch electrodes E1and each of the second touch electrodes E2, the sensor pitches thereof are respectively 4.5 mm-5.5 mm or so. The size of the sensing area S is a square of 4.5 mm-5.5 mm or so. However, the values are exemplarily for depiction purpose only, not to limit the invention and the people skilled in the art can adjust the values according to the design requirement.

FIG. 7is a time sequence diagram of an in-cell touch display panel according to an embodiment of the invention.FIG. 7only schematically illustrates operating time sequences of the data lines110, the scan lines120, and the second touch electrodes E2, not showing the details of other components of the in-cell touch display panel10, where1, n and m are positive integers. Referring toFIGS. 1,2,5, and7, by the structure design of the active device array substrate100, the in-cell touch display panel10of the embodiment can achieve displaying and touching functions. Specifically, a display cycle and a touching cycle of the in-cell touch display panel10of the embodiment are not overlapped with each other. In other words, the display cycle and the touching cycle are present, for example, on the basis of time division mode.

In the display cycle, each of the scan lines120is sequentially enabled so as to turn on the corresponding active device130, and each of the data signal lines110is also independently enabled. The signals are delivered to the corresponding pixel electrodes140through the sources136, the channel layer134and the drains138. At the time, all the common electrodes150transmit the signals through the common signal lines170and have a common electrical potential. Meanwhile, a lateral electrical field can be formed between the pixel electrodes140and the corresponding common electrodes150to drive display medium in the display medium layer300and further realize the displaying function of the in-cell touch display panel10.

In the touching cycle, the second touch electrodes E2are sequentially driven, in which when each of the second touch electrodes E2is driven, all the data signal lines110corresponding to each of the second touch electrodes E2are driven simultaneously. In more details, the data signal lines110connected to the switch160are electrically connected together through the same switch160. As a result, the sensing signals can be simultaneously transmitted to the data signal lines110connected to the same switch160. In other words, all the pixel electrodes140forming of the same second touch electrodes E2can be simultaneously enabled to have a same electrical potential. At the time, each of the second touch electrodes E2transmits the signal through the data signal line110. There is an insulation layer145located between the first touch electrode E1and the second touch electrode E2at the overlapping place, so that a capacitance is present in the sensing area S at the overlapping place of the first touch electrode E1and the second touch electrode E2. When a touch event occurs, the capacitance of the touched sensing area S gets changed and the touch position can be revealed by detection, and the touching function of the in-cell touch display panel10is therefore achieved. Specifically, the display cycle and the touching cycle are present alternately, in which the time length of the display cycle is greater than the time length of the touching cycle.

In another embodiment, the active device array substrate100further includes a plurality of conductive patterns180electrically connected to the common electrodes150. In more details, prior to forming the common electrodes150, a plurality of conductive patterns180are formed on the insulation layer145. The conductive patterns180and the common electrodes150contact each other, as shown inFIG. 6. In the embodiment, the disposing positions of the conductive patterns180, preferably, are corresponding to the distribution positions of the black matrix layer on the opposite substrate200, which can reduce the probability for the user to see the conductive patterns180. In addition, the conductive patterns180, preferably, are made of metallic material or other conductive materials with good conductivity. In this way, the conduction impedance of the first touch electrodes E1can be reduced and the touching sensitivity of the first touch electrodes E1can be thereby advanced.

In summary, when the in-cell touch display panel of the invention is in the display cycle, each of the data signal lines is independently enabled so that the common electrodes and the pixel electrodes drive the display medium layer to realize the general displaying function; in the touching cycle, the data signal lines connected to the same switch are simultaneously enabled so that the pixel electrodes and the data signal lines connected to the same switch together form the second touch electrodes. The common electrodes form the first touch electrodes. A plurality of sensing areas can be formed at the overlapping place of the alternately disposed first touch electrodes and second touch electrodes. In other words, the pixel electrodes can realize the touching function through the design of the data signal lines and the switch.