Light emitting diode touch display device

Abstract

This invention provides a light-emitting diode (LED) touch display device comprising a thin-film transistor (TFT) substrate, a light-emitting element, a plurality of sensing electrode pads, and patterned electrodes. The TFT substrate has a substrate and transistors disposed on the substrate. The light-emitting element has a first terminal electrode electrically connected to the transistor, a light-emitting layer, and a second terminal electrode. The light-emitting layer is sandwiched between the first terminal electrode and the second terminal electrode. The plurality of sensing electrode pads are disposed on the second terminal electrode. The patterned electrodes are disposed on the second terminal electrode and overlap with the sensing electrode pads.

Description

[0001] This application is a divisional application of Chinese invention patent application filed on August 22, 2016, with application number "201610700808.X" and invention title "Light Emitting Diode Touch Display Device". Technical Field

[0002] This invention relates to a touch display device, and more particularly to a light-emitting diode touch display device. Background Technology

[0003] With the continuous advancement of technology, various information devices are constantly being innovated, such as mobile phones, tablets, ultra-thin laptops, and satellite navigation systems. Besides the usual keyboard or mouse input and control, using touch technology to operate information devices is a highly intuitive and popular method. Touch devices offer a user-friendly and intuitive input interface, allowing users of any age to directly select or control information devices with their fingers or a stylus.

[0004] Most current touch technologies are two-dimensional (2D) multi-touch, which uses, for example, a finger touching the display surface to accurately determine the finger's touch position, thereby generating corresponding control functions. In addition to 2D touch technologies, capacitive pressure sensing technology is generally used to sense the pressure applied in the Z-axis direction perpendicular to the display surface, thereby generating corresponding control functions. Summary of the Invention

[0005] This invention provides a light-emitting diode (LED) touch display device, including a thin-film transistor (TFT) substrate and a light-emitting element. The TFT substrate has a substrate and a TFT structure disposed on the substrate, the TFT structure including a driving transistor. The light-emitting element is disposed on the TFT structure and has a first terminal electrode, a light-emitting layer, and a second terminal electrode. The first terminal electrode is electrically connected to the driving transistor, and the light-emitting layer is sandwiched between the first terminal electrode and the second terminal electrode. The first terminal electrode or the second terminal electrode serves as a touch sensing electrode for the LED touch display device.

[0006] In one embodiment, the driving modes of the LED touch display device include a full-time driving mode and a time-sharing driving mode.

[0007] In one embodiment, in time-sharing driving mode, a frame time of the LED touch display device includes a display period and a sensing period.

[0008] In one embodiment, a first endpoint electrode is connected to a first power line, a second endpoint electrode is connected to a second power line, and during the sensing period, at least one first pulse signal is transmitted to the touch sensing electrode, and at least one second pulse signal is transmitted to the first power line or the second power line.

[0009] In one embodiment, the driving transistor is in the off state during sensing.

[0010] In one embodiment, a first terminal electrode is connected to a first power line, a second terminal electrode is connected to a second power line, and during sensing, the voltage applied to the first power line is less than the voltage applied to the second power line.

[0011] In one embodiment, the touch sensing electrode includes a plurality of electrode pads, each electrode pad being electrically connected to at least one trace.

[0012] In one embodiment, the LED touch display device further includes a reference electrode that is disposed corresponding to the electrode pads of the touch sensing electrode.

[0013] In one embodiment, the LED touch display device further includes a flexible layer located between the reference electrode and the touch sensing electrode.

[0014] In one embodiment, a portion of the electrode pads is used to sense touch signals in a first direction and a second direction, and another portion of the electrode pads is used to sense touch signals in a third direction that is perpendicular to the first direction and the second direction, respectively.

[0015] The present invention also provides a light-emitting diode touch display device, comprising a thin-film transistor substrate, a light-emitting element, and a touch-sensing electrode. The thin-film transistor substrate has a substrate and a thin-film transistor structure disposed on the substrate, the thin-film transistor structure including a driving transistor. The light-emitting element is disposed on the thin-film transistor structure and has a first terminal electrode, a light-emitting layer, and a second terminal electrode. The first terminal electrode is electrically connected to the driving transistor, and the light-emitting layer is sandwiched between the first terminal electrode and the second terminal electrode. The touch-sensing electrode is disposed on the second terminal electrode or between the first terminal electrode and the substrate, and is correspondingly disposed to the first or second terminal electrode.

[0016] The present invention provides a light-emitting diode touch display device, comprising a thin-film transistor substrate, a light-emitting element, and a reference electrode. The thin-film transistor substrate has a substrate and a thin-film transistor structure disposed on the substrate, the thin-film transistor structure including a driving transistor. The light-emitting element is disposed on the thin-film transistor structure and has a first terminal electrode, a light-emitting layer, and a second terminal electrode. The first terminal electrode is electrically connected to the driving transistor, and the light-emitting layer is sandwiched between the first terminal electrode and the second terminal electrode. The reference electrode is disposed corresponding to either the first terminal electrode or the second terminal electrode.

[0017] In one embodiment, a first endpoint electrode or a second endpoint electrode is used as a touch sensing electrode of the LED touch display device. The touch sensing electrode includes a plurality of electrode pads, each of which is electrically connected to at least one trace.

[0018] As described above, in the LED touch display device of the present invention, the first or second terminal electrode of the light-emitting element is used as the touch sensing electrode of the LED touch display device; or the touch sensing electrode is disposed on the second terminal electrode or between the first terminal electrode and the substrate, and is correspondingly disposed with respect to the first or second terminal electrode; or a reference electrode is further disposed, and is correspondingly disposed with respect to the first or second terminal electrode. Through the above structure, the present invention integrates the process of the touch sensing electrode into the process of a thin-film transistor, and utilizes a self-capacitance touch method, integrating the circuit for controlling the touch function and the circuit for controlling the display function into the same control integrated circuit (IC), thereby reducing the cost of the external touch panel process and the control IC, making the LED touch display device of the present invention have the advantages of simplified process and fewer components. Attached Figure Description

[0019] Figure 1A This is a partial cross-sectional schematic diagram of a light-emitting diode touch display device according to an embodiment of the present invention.

[0020] Figure 1B This is an equivalent circuit diagram of a pixel structure of a light-emitting diode touch display device according to an embodiment of the present invention.

[0021] Figure 1C This is a timing diagram of the time-sharing driving mode of a light-emitting diode touch display device according to an embodiment of the present invention.

[0022] Figure 1D This is a top view schematic diagram of a touch sensing electrode according to an embodiment of the present invention.

[0023] Figures 2A to 2C These are partial cross-sectional schematic diagrams of LED touch display devices according to different embodiments of the present invention.

[0024] Figure 3 This is a partial cross-sectional schematic diagram of a light-emitting diode touch display device according to another embodiment of the present invention.

[0025] Figures 4A to 4C These are schematic diagrams of reference electrodes for different embodiments of the present invention.

[0026] Figure 5A and Figure 5B These are top views of touch sensing electrodes and reference electrodes in different implementations.

[0027] Figure 6A This is a schematic diagram of the control circuit for an LED touch display device when there is no touch input.

[0028] Figure 6B This is a schematic diagram of the control circuit for a light-emitting diode touch display device when it has touch in a first direction and a second direction.

[0029] Figure 6C This is a schematic diagram of the control circuit for a light-emitting diode touch display device that has touch control in three directions simultaneously.

[0030] Figure 6D This is a waveform diagram of the output touch signal.

[0031] Figure 7A , Figure 7C , Figure 7D and Figure 7E These are partial cross-sectional schematic diagrams of LED touch display devices according to different embodiments of the present invention.

[0032] Figure 7B for Figure 7A The equivalent circuit diagram of a pixel structure of a light-emitting diode touch display device. Detailed Implementation

[0033] The following description, with reference to the accompanying drawings, illustrates some embodiments of a light-emitting diode touch display device according to the present invention, wherein the same elements are described using the same reference numerals. All illustrations of the embodiments of the present invention are merely schematic and do not represent actual dimensions or proportions. Furthermore, the terms "above" and "below" used in the following embodiments are only used to indicate relative positional relationships. Moreover, the formation of one element "above," "on top of," "below," or "below" another element may include one element being in direct contact with another element in the embodiments, or it may include situations where there are other additional elements between one element and another element so that one element is not in direct contact with the other element.

[0034] Please refer to Figures 1A to 1D As shown, where, Figure 1A This is a partial cross-sectional schematic diagram of a light-emitting diode touch display device 1 according to an embodiment of the present invention. Figure 1B This is an equivalent circuit diagram of a pixel structure of a light-emitting diode touch display device 1 according to an embodiment of the present invention. Figure 1C This is a timing diagram illustrating the time-division driving mode of a light-emitting diode touch display device 1 according to an embodiment of the present invention. Figure 1D This is a top view schematic diagram of a touch sensing electrode according to an embodiment of the present invention.

[0035] The light-emitting diode touch display device 1 is an active matrix light-emitting diode (AMLED) touch display device, such as a smartphone, tablet computer, ultra-thin laptop computer or wearable device, or other display with touch function, and is not limited thereto.

[0036] like Figure 1A As shown, the LED touch display device 1 includes a thin-film transistor substrate 11 and at least one light-emitting element 12. Furthermore, the LED touch display device 1 of this embodiment further includes a pixel definition layer (PDL), a protective layer (BP), a trace (C), a flexible layer (FL), and a protective substrate (CM).

[0037] The thin-film transistor substrate 11 has a substrate 111 and a thin-film transistor structure 112 disposed on the substrate 111. The substrate 111 can be a rigid plate or a flexible plate, and can be light-transmitting or light-opaque. The rigid plate is, for example, glass, while the flexible plate is, for example, a flexible substrate with flexibility, and its material is, for example, but not limited to, polyimide (PI). Furthermore, the thin-film transistor structure 112 has multiple transistor structures corresponding to multiple light-emitting elements 12, and these transistor structures, together with the light-emitting elements 12, form multiple pixel structures and are arranged in a two-dimensional array matrix.

[0038] Here, as Figure 1BAs shown, the equivalent circuit of a pixel structure is exemplified by a 2T1C circuit, including a control transistor T1, a driving transistor T2, a storage capacitor CS, and a light-emitting element 12. The gate of the control transistor T1 is connected to a scan line SL, the first terminal of the control transistor T1 is connected to a data line DL, and the second terminal of the control transistor T1 is connected to the gate of the driving transistor T2. The first terminal of the driving transistor T2 is connected to a first power supply VDD via a first power supply line C1. The two ends of the storage capacitor CS are connected to the gate of the driving transistor T2 and the first terminal of the driving transistor T2, respectively. The second terminal of the driving transistor T2 is connected to the anode of the light-emitting element 12, and the cathode of the light-emitting element 12 is connected to a second power supply VSS via a second power supply line C2. In this embodiment, the touch capacitance CT is the change in self-capacitance generated by the touch sensing electrode when the user touches the photodiode touch display device 1. In this embodiment, the control transistor T1 and the driving transistor T2 are both PMOS transistors. Of course, in different embodiments, the control transistor T1 and the driving transistor T2 can also be NMOS transistors, and are not limited thereto. In addition, in different embodiments, the equivalent circuit of the pixel structure can also be, for example, 4T2C, or 5T1C, 6T1C, 7T2C, or others, and are not limited thereto.

[0039] In addition, Figure 1A The image shows the structure of the driving transistor T2 and the light-emitting element 12 in the thin-film transistor structure 112 within a pixel structure. Figure 1A The control transistor T1 and the storage capacitor CS are not shown. The light-emitting element 12 is disposed on the thin-film transistor structure 112 and has a first terminal electrode 121, a second terminal electrode 122, and a light-emitting layer 123. The first terminal electrode 121 is electrically connected to the second terminal of the driving transistor T2, and the light-emitting layer 123 is sandwiched between the first terminal electrode 121 and the second terminal electrode 122. Here, the light-emitting element 12 is an organic light-emitting diode (OLED) or a light-emitting diode (LED), and when forward biased, the light-emitting element 12 can emit light.

[0040] In addition to the driving transistor T2, the thin-film transistor structure 112 further includes a buffer layer B, a first dielectric layer ILD1, a second dielectric layer ILD2, and a planarization layer PLN.

[0041] A buffer layer B is disposed on the substrate 111, and a driving transistor T2 is disposed on the buffer layer B. The driving transistor T2 includes a gate G, a gate insulating layer GI, a channel layer A, a first electrode E1, and a second electrode E2. Here, the driving transistor T2 is an example of a top-gate type thin-film transistor. In different embodiments, the driving transistor T2 may also be a bottom-gate type thin-film transistor, and is not limited thereto.

[0042] A gate insulating layer GI is disposed on a buffer layer B, and a channel layer A is disposed on the gate insulating layer GI relative to the gate G. In this embodiment, the gate insulating layer GI is disposed on and covers the channel layer A. The material of the gate insulating layer GI is, for example, a silicon oxide compound, or an inorganic material such as silicon nitride, silicon oxide, silicon oxynitride, silicon carbide, aluminum oxide, hafnium oxide, or a multilayer structure of the above materials. In addition, in practice, the channel layer A may, for example, include a low-temperature polysilicon (LTPS), amorphous silicon, or a metal oxide. Among them, the aforementioned metal oxide is, for example, but not limited to, indium gallium zinc oxide (IGZO).

[0043] First electrode E1 and second electrode E2 are respectively disposed on channel layer A, and one end of first electrode E1 and second electrode E2 are in contact with channel layer A. When channel layer A of driving transistor T2 is not turned on, first electrode E1 and second electrode E2 are electrically separated. The material of first electrode E1 and second electrode E2 can be a single-layer or multi-layer structure made of metal (e.g., aluminum, copper, silver, molybdenum, or titanium) or its alloy. First electrode E1 and second electrode E2 can also be transparent conductive layers (e.g., ITO, IZO, or ITZO, etc.). In addition, some wires used to transmit driving signals can use a structure of the same layer and the same process as first electrode E1 and second electrode E2, such as data lines ( Figure 1A (Not displayed).

[0044] The gate G is disposed on the gate insulating layer GI and opposite to the channel layer A. Here, the gate G is located above the channel layer A. The gate G can be a single-layer or multi-layer structure made of a metal (e.g., aluminum, copper, silver, molybdenum, or titanium) or its alloy. The gate G can also be a transparent electrode layer (e.g., ITO, IZO, or ITZO, etc.). Some of the wires used to transmit drive signals can use a structure of the same layer and process as the gate G, and are electrically connected to each other, such as scan lines. Figure 1A (Not shown). In addition, the first dielectric layer ILD1 covers the gate insulating layer GI and the gate G, and the second dielectric layer ILD2 covers the first dielectric layer ILD1.

[0045] In addition, in this embodiment, the first electrode E1 and the second electrode E2 are in contact with the channel layer A through a via (not shown) in the gate insulating layer GI, the first dielectric layer ILD1, and the second dielectric layer ILD2, respectively. In different embodiments, one end of the first electrode E1 and the second electrode E2 may also be in contact with the channel layer A through an opening in an etch stop layer, which is not limited.

[0046] A planarization layer PLN is disposed and covers the second dielectric layer ILD2, and a first endpoint electrode 121 is disposed on the planarization layer PLN and connected to the second electrode E2 through a through-hole (not shown) in the planarization layer PLN. Additionally, a pixel definition layer PDL is disposed on the first endpoint electrode 121 and fills the through-hole in the planarization layer PLN. A light-emitting layer 123 and a second endpoint electrode 122 are sequentially stacked on the first endpoint electrode 121, with the second endpoint electrode 122 covering the pixel definition layer PDL. In this embodiment, the first endpoint electrode 121 is, for example, the anode of the light-emitting element 12, and the second endpoint electrode 122 is, for example, the cathode of the light-emitting element 12. However, in different embodiments, the first endpoint electrode 121 may also be a cathode, and the second endpoint electrode 122 may be an anode; this invention is not limited to these embodiments.

[0047] The materials of the first terminal electrode 121 and the second terminal electrode 122 can be, for example, ITO, IZO, AZO, CTO, SnO2, ZnO, ITO / Ag / ITO, or magnesium alloy, etc., and are not limited. In some embodiments, when the LED touch display device 1 emits light upwards, the first terminal electrode 121 can be an opaque metal material, and the second terminal electrode 122 can be a light-transmitting material; when the LED touch display device 1 emits light downwards, the first terminal electrode 121 can be a light-transmitting material, and the second terminal electrode 122 can be an opaque metal material.

[0048] Furthermore, the protective substrate CM is disposed opposite to the substrate 111, and the thin-film transistor structure 112 and the light-emitting element 12 are sandwiched between the protective substrate CM and the substrate 111. The protective substrate CM can be a rigid board or a flexible board; a rigid board is, for example, glass, while a flexible board is, for example, a flexible substrate. Additionally, the protective layer BP is an insulating layer, disposed on and covering the second terminal electrode 122, and the trace C is disposed on the protective layer BP, passing through a through-hole H in the protective layer BP, and connecting to the second terminal electrode 122. Here, the trace C is located on the upper side of the second terminal electrode 122; in different embodiments, the trace C may also be located on the lower side of the second terminal electrode 122, or on the upper or lower side of the first terminal electrode 121, and is not limited thereto. Furthermore, a sealant (not shown) encloses the flexible layer FL between the protective substrate CM and the protective layer BP. The frame adhesive is, for example, UV adhesive or frit, while the flexible layer FL is, for example, an air layer containing nitrogen or an inert gas, a flexible material layer, such as, but not limited to, optical adhesive (OCA / LOCA), optically transparent resin (OCR), optically elastic resin (SVR), silicone, or polyimide (PI), or an inorganic composite layer (inorganic / organic / inorganic). In this invention, the flexible layer FL can be deformed by pressure and has restoring force, and is not limited thereto.

[0049] Therefore, when the scan lines SL of the LED touch display device 1 receive scan signals and turn on the control transistor T1 respectively, the corresponding data lines DL can receive data signals to charge the storage capacitor CS, so that the storage voltage of the storage capacitor CS can control the driving transistor T2 to conduct, so that the first power supply VDD (e.g. +5V) and the second power supply VSS (e.g. 0V) make the light-emitting elements 12 of each pixel structure forward biased and emit light, so that the LED touch display device 1 can display image screen.

[0050] To save on the manufacturing process of the touch panel and use fewer components, either the first endpoint electrode 121 or the second endpoint electrode 122 can be used as a touch sensing electrode for the LED touch display device 1. This embodiment uses the second endpoint electrode 122 as the touch sensing electrode for the LED touch display device 1 to sense the user's touch action, making the LED touch display device 1 an in-cell LED touch display device, and utilizing a touch control method based on self-capacitance changes. Therefore, in this embodiment, the circuitry controlling the touch function and the circuitry controlling the display function can be integrated into the same control integrated circuit (IC), thereby reducing the manufacturing process and materials of the touch panel, as well as the cost of the control IC. The aforementioned touch sensing electrode (i.e., the second endpoint electrode 122) can sense touch functions in two directions (the first direction X and the second direction Y, the XY plane).

[0051] Please refer to the following: Figure 1D As shown, the second terminal electrode 122 (cathode) of the light-emitting element 12 is used as the touch sensing electrode. Here, the second terminal electrode 122 can be fabricated into a patterned electrode pattern to serve as a sensing electrode pad. In this embodiment, the touch sensing electrode of the LED touch display device 1 includes multiple electrode pads P, each electrode pad P being electrically connected to at least one trace C. In this embodiment, the trace C can provide a second power supply VSS during display and provide a driving (sensing) signal to the electrode pads P of the touch sensing electrode during (touch) sensing. These electrode pads P can be configured in a two-dimensional array, and each electrode pad P can correspond to one or more pixel structures (corresponding to one or more light-emitting elements 12), without limitation. In different embodiments, if the first terminal electrode 121 (anode) of the light-emitting element 12 is used as the touch sensing electrode, the second terminal electrode 122 of each light-emitting element 12 is itself patterned; therefore, one electrode pad P can correspond to one pixel structure.

[0052] exist Figure 1D In the middle, each electrode pad P is perforated by 3 holes H (corresponding to Figure 1A The perforations H) are electrically connected to the trace C (that is, the trace C is electrically connected to the electrode pad P of the touch sensing electrode (second endpoint electrode 122) through the three perforations H). Therefore, when a finger touches the protective substrate CM and causes the capacitance value sensed by the electrode pad P to change, the electrical signal can be transmitted to the control IC through the trace C to determine the location of the touch and generate the corresponding control action.

[0053] Furthermore, in this embodiment, the driving mode of the LED touch display device 1 can include a full-time driving mode and a time-division driving mode. In the full-time driving mode, the touch sensing electrode (second endpoint electrode 122) can provide multiple driving signals TP, such as pulses, within the frame time FT, thereby obtaining a touch signal indicating the capacitance change of the touch capacitor CT. In the time-division driving mode, such as... Figure 1C As shown, each frame time FT of the LED touch display device 1 may include a display period DT and a sensing period ST. The display period DT is the time for transmitting a scan signal SN to the scan line SL and a data signal DN to the data line DL to display the image. The sensing period ST is the time for transmitting a drive signal TP (in this embodiment, the drive signal TP is the signal of the second power supply VSS) to the touch sensing electrode to sense the time of user touch.

[0054] During the sensing period ST in the time-division driving mode, preferably, at least one first pulse signal PL1 (i.e., drive signal TP) is transmitted to the touch sensing electrode, and at least one second pulse signal PL2 is transmitted to the first power line C1 or the second power line C2, and the first pulse signal PL1 and the second pulse signal PL2 correspond to each other. Here, "correspond to each other" means that the first pulse signal PL1 and the second pulse signal PL2 are transmitted at the same time, and their pulse magnitudes (voltage differences) are also the same. In this embodiment, the first pulse signal PL1 (i.e., drive signal TP) transmitted to the touch sensing electrode corresponds to the second pulse signal PL2 of the first power supply VDD transmitted through the first power line C1.

[0055] In other words, the signal of the first power supply VDD follows the changes in the drive signal TP transmitted to the touch sensing electrode. This is because if only the drive signal TP (first pulse signal PL1) is transmitted to the touch sensing electrode, it will change the current flowing through the light-emitting element 12, thus affecting its light-emitting effect. Therefore, the waveform of the second pulse signal PL2 of the first power supply VDD must correspond exactly to the waveform of the first pulse signal PL1 transmitted to the touch sensing electrode. This reduces the consequences of changes in the current flowing through the light-emitting element 12, ensuring that the drive signal TP transmitted to the touch sensing electrode does not affect the light-emitting effect of the light-emitting element 12. More preferably, during the sensing period ST, the waveform of the scan signal SN transmitted to the scan line SL and the waveform of the data signal DN transmitted to the data line DL correspond exactly to the waveforms of the drive signal TP (second power supply VSS) and the first power supply VDD, further preventing excessive load on the touch sensing electrode and affecting the touch quality of the LED touch display device.

[0056] In some embodiments, the driving transistor T2 can be controlled to be in the off state during the sensing period ST, so that the light-emitting element 12 does not emit light. In this way, the driving signal TP transmitted during the sensing period ST will not affect the light emission of the light-emitting element 12. Specifically, during the sensing period ST, the voltage applied to the first power line C1 (i.e., the first power supply VDD) can be less than the voltage applied to the second power line C2 (i.e., the second power supply VSS). For example, the first power line C1 can be directly grounded, making the voltage of the first power supply VDD 0 volts, thereby making the light-emitting element 12 non-forward biased, or further reverse biased and not emitting light, so as to avoid affecting the light emission effect of the light-emitting element 12. Alternatively, the first power line C1 can be floated, and the present invention is not limited to either. In some embodiments, a switching transistor can also be connected in series at the second terminal of the driving transistor T2 to control the light emission of the light-emitting element 12.

[0057] However, in order to compensate for the fact that the light-emitting element 12 does not emit light during the sensing period ST, in some embodiments, the light-emitting element 12 can be driven to emit light in an overdrive manner during the display period DT (increasing its transverse voltage), so that the brightness of the light-emitting element 12 is higher. The overdrive method is used to compensate for the situation that the light-emitting element 12 does not emit light during the sensing period ST, so that the average brightness of a frame time FT is the same as the average brightness of a whole frame when it is fully lit, thus not affecting the overall display effect.

[0058] Furthermore, it should be noted that, regardless of whether it is a full-time driving mode or a time-sharing driving mode, in the known technology used in the thin-film transistors used to manufacture the active-matrix LED touch display device 1, the threshold voltage (Vth) of the driving transistor may shift due to factors such as different processes, materials, or component characteristics. This indirectly causes slight differences in the driving current of each pixel structure's LED under the same data voltage, resulting in uneven brightness of the displayed image in the LED touch display device 1 (e.g., mura). To improve the above phenomenon, in some embodiments, a pixel compensation circuit can be used to compensate for the uneven brightness caused by the shift in the threshold voltage (Vth) of the driving transistor.

[0059] Please refer to the following respectively Figures 2A to 2C The figures shown are partial cross-sectional schematic diagrams of LED touch display devices 1a to 1c, which are different embodiments of the present invention.

[0060] like Figure 2A As shown, with Figure 1A The main difference is that, Figure 2A The LED touch display device 1a does not have a protective layer BP, and the trace C uses the same process and material as the first endpoint electrode 121. The through hole H is located in the pixel definition layer PDL, so that the material of the second endpoint electrode 122 can be filled into the through hole H and electrically connected to the trace C located on the lower side of the second endpoint electrode 122.

[0061] In addition, such as Figure 2B As shown, with Figure 1A The main difference is that, Figure 2B The LED touch display device 1b also does not have a protective layer BP. The trace C is disposed on the second dielectric layer ILD2 using the same process and materials as the first electrode E1 or the second electrode E2. The through hole H is located on the pixel definition layer PDL and the planarization layer PLN, so that the material of the second terminal electrode 122 can be filled into the through hole H and electrically connected to the trace C located on the second dielectric layer ILD2.

[0062] In addition, such as Figure 2CAs shown, with Figure 2B The main difference is that, Figure 2C In the LED touch display device 1c, the through-hole H1 of the planarization layer PLN is filled with the same material as the first endpoint electrode 121, and the through-hole H2 of the pixel definition layer PDL is filled with the same material as the second endpoint electrode 122 and electrically connected to the material in the through-hole H1, so that the second endpoint electrode 122 is connected to the trace C through the through-holes H1 and H2. In some embodiments, the through-holes H1 and H2 may be misaligned and not overlap.

[0063] Furthermore, other technical features and driving and control methods of LED touch display devices 1a to 1c can be referred to the same components of LED touch display device 1, and will not be repeated here.

[0064] Please refer to Figure 3 As shown, it is a partial cross-sectional schematic diagram of a light-emitting diode touch display device 1d according to another embodiment of the present invention.

[0065] and Figure 1A The main difference between the LED touch display device 1 and the LED touch display device 1d in this embodiment is that, in addition to having all the components, structures and driving control methods of the LED touch display device 1, the LED touch display device 1d in this embodiment also includes a reference electrode 14, which is correspondingly disposed with the electrode pads of the touch sensing electrode (i.e., the second terminal electrode 122).

[0066] In some embodiments, the reference electrode 14 may be as follows: Figures 4A to 4C The reference electrode 14 may be a patterned electrode, or it may not be patterned but rather a single electrode covering an entire surface; this is not limited. The reference electrode 14 may be disposed on the upper or lower surface of the protective substrate CM; or the metal frame or metal film of the display device itself may be used as the reference electrode 14, and its material may be transparent (e.g., ITO) or opaque (metal, metal film layer), without limitation. In this embodiment, the reference electrode 14 is disposed on the lower surface of the protective substrate CM, and its material is, for example, a transparent conductive material. A sensing capacitor can be formed by sandwiching a flexible layer FL between the reference electrode 14 and the touch sensing electrode (i.e., the second endpoint electrode 122) to sense a third direction Z of pressure. The third direction Z is perpendicular to both the first direction X and the second direction Y (XY plane).

[0067] Therefore, as described above, the touch sensing electrode (i.e., the second endpoint electrode 122) can sense touch actions in two directions (XY plane), and the reference electrode 14 can form multiple sensing capacitors with the electrode pads P to sense the third direction Z.

[0068] Please refer to the following respectively Figure 5A and Figure 5B As shown, these are top views of touch sensing electrodes and reference electrodes in different implementations.

[0069] In some embodiments, such as Figure 5A As shown, it is using, as Figure 1D These electrode pads P are used to sense touch signals in three directions. In other words, sensing touch signals in three directions is also achieved through these electrode pads P, that is, the touch function of sensing the third direction Z is integrated with the touch function of sensing the first direction X and the second direction Y by the control IC.

[0070] Alternatively, in some embodiments, such as Figure 5B As shown, one portion of electrode pad P1 is used to sense touch signals in the first direction X and the second direction Y (XY plane), while the other portion of electrode pad P2 is used to sense touch signals in the third direction Z. Here, electrode pad P1, used to sense touch signals in the XY plane, is generally rectangular, while electrode pad P2, used to sense touch signals in the third direction Z, is elongated. However, the shape of the electrode pads can be varied according to design requirements and is not limited to the shape disclosed in this embodiment. Electrode pads P1 and P2 are also connected to a control IC via at least one trace C, enabling... Figure 5B The number of traces C is relatively Figure 5A In other words, the touch signals sensing the XY plane are achieved through the generally rectangular electrode pads P1, but the touch signals sensing the third direction Z are achieved through other generally elongated electrode pads P2. That is, the touch function sensing the third direction Z is separated from the touch function sensing the first direction X and the second direction Y by the control IC. In addition, the elongated electrode pads P2 are located between two adjacent electrode pads P1.

[0071] Furthermore, other technical features and driving and control methods of the LED touch display device 1d can be referred to the LED touch display device 1 described above, and will not be repeated here.

[0072] Please refer to the following respectively. Figures 6A to 6D As shown, where, Figure 6A This is a schematic diagram of the control circuit for the LED touch display device 1d when there is no touch input. Figure 6B This is a schematic diagram of the control circuit for a light-emitting diode touch display device 1d when there is touch in the first direction X and the second direction Y (XY plane). Figure 6C This is a schematic diagram of the control circuit for a light-emitting diode touch display device 1d that simultaneously supports touch in three directions (XYZ). Figure 6D This is a waveform diagram of the output touch signal (Vout).

[0073] like Figure 6A As shown, the capacitive signal without touch control can be as follows:

[0074]

[0075] In addition, such as Figure 6B As shown, the capacitive signal under touch in the XY plane (two-dimensional) is as follows:

[0076]

[0077] In addition, such as Figure 6C As shown, the capacitive signals under simultaneous touch control in the XY plane and the Z direction (three dimensions) are as follows:

[0078]

[0079] Wherein, Ctp is the inherent capacitance of the sensing electrode for sensing two-dimensional touch, Cp is the inherent capacitance of the sensing electrode for sensing three-dimensional touch, and Cf is, for example, the (touch) capacitance generated after a finger touches the surface.

[0080] In addition, such as Figure 6D As shown, for example, 100 units is the touch threshold value for XY plane touch, and 250 units is the touch threshold value for simultaneous XYZ direction (3D) touch. Both of these touch threshold values ​​are greater than the background value (60) when there is no touch. Figure 6D As can be seen, a touch in the XY plane was detected at time t1, and a touch in the third direction (Z) was detected at time t2. Moreover, the touch signal (Vout) value output when there is a touch in the three-dimensional direction is greater than the touch signal value when there is only an XY plane touch. By using the value of the touch signal (Vout), the control circuit can distinguish whether the touch is in the XY plane or in the XYZ direction, thereby generating the corresponding control action.

[0081] It should be further noted that in some embodiments, the protective substrate CM is generally thicker, for example, 0.5 mm, while the flexible layer FL is relatively thinner, for example, 100 micrometers or less. Since the thickness of the protective substrate CM is much greater than the thickness of the flexible layer FL, the capacitance change between the reference electrode 14 and the electrode pads P is much greater than the capacitance change between the finger and the electrode pads P during a third-party touch or press towards Z. Therefore, the capacitance change caused by the finger can be ignored.

[0082] In addition, please refer to the following: Figures 7A to 7E As shown, where, Figure 7A , Figure 7C , Figure 7D and Figure 7E These are partial cross-sectional schematic diagrams of LED touch display devices 1e to 1h, representing different embodiments of the present invention. Figure 7B for Figure 7AThe equivalent circuit diagram of a pixel structure of the LED touch display device 1e.

[0083] like Figure 7A As shown, the LED touch display device 1e and Figure 2A The main difference between the LED touch display device 1a and the LED touch display device 1e is that the LED touch display device 1e does not use the second terminal electrode 122 as the touch sensing electrode, but instead provides another touch sensing electrode 13 within the thin-film transistor structure 112. The touch sensing electrode 13 can be disposed on the second terminal electrode 122 or between the first terminal electrode 121 and the substrate 111, corresponding to either the first terminal electrode 121 or the second terminal electrode 122. In this embodiment, the touch sensing electrode 13 is disposed on the substrate 111 and located between the buffer layer B and the substrate 111, corresponding to the second terminal electrode 122. Furthermore, a protective layer BP1 covers the touch sensing electrode 13, and a trace C is disposed on the protective layer BP1, filling the through-holes in the protective layer BP1 to connect with the touch sensing electrode 13. Additionally, another protective layer BP2 covers the trace C and the protective layer BP1, and is located between the buffer layer B and the protective layer BP1.

[0084] The touch sensing electrode 13 may include multiple electrode pads P of the touch sensing electrode in the above embodiment. The specific technical details have been described in detail above and will not be repeated here. In addition, the LED touch display device 1e in this embodiment also includes the above-described full-time driving mode and time-sharing driving mode. Please refer to the above for the specific technical details as well, and they will not be repeated here.

[0085] In addition, such as Figure 7B The diagram shown is an equivalent circuit diagram of a pixel structure of a light-emitting diode touch display device 1e. Here, the cathode of the light-emitting element 12 is connected to the second power supply VSS, and one end of the touch capacitor CT is connected to the anode of the light-emitting element 12. However, in different embodiments, if the touch sensing electrode 13 is disposed above the second terminal electrode 122, the cathode of the light-emitting element 12 can be connected to the second power supply VSS, and one end of the touch capacitor CT can be connected to the cathode of the light-emitting element 12; this is not a limitation.

[0086] exist Figure 7B During the sensing period ST in the time-division driving mode, the touch sensing electrode 13 can provide multiple driving signals TP, such as pulses, within the frame time FT. Preferably, during the sensing period ST, the signal waveforms transmitted to the scan line SL and data line DL, the second power supply VSS, and the first power supply VDD can correspond to the same signal waveform as the driving signal TP, so as to avoid changes in the current flowing through the light-emitting element 12 from affecting the display effect of the LED touch display device 1e.

[0087] Furthermore, other technical features and driving and control methods of the LED touch display device 1e can be referred to the LED touch display device 1 described above, and will not be repeated here.

[0088] In addition, such as Figure 7C As shown, with Figure 7A The main difference between the LED touch display device 1e and the LED touch display device 1f is that the LED touch display device 1f has only one protective layer BP. In this embodiment, the trace C is disposed on the substrate 111, and the protective layer BP covers the trace C. The touch sensing electrode 13 is disposed between the buffer layer B and the protective layer BP, and is electrically connected to the trace C through the through-hole in the protective layer BP.

[0089] In addition, such as Figure 7D As shown, the main difference between this and the LED touch display device 1f is that the touch sensing electrode 13 of the LED touch display device 1g is disposed on the second dielectric layer ILD2. Specifically, the trace C is first disposed on the second dielectric layer ILD2, then the protective layer BP is covered on the trace C, and then the touch sensing electrode 13 is disposed on the protective layer BP and electrically connected to the trace C through a through-hole in the protective layer BP. Furthermore, the planarization layer PLN completely covers the touch sensing electrode 13 and the protective layer BP.

[0090] In addition, such as Figure 7E As shown, with Figure 7A The main difference between the LED touch display device 1e and the LED touch display device 1h is that the latter further includes a reference electrode 14, which is correspondingly disposed with the electrode pads P of the touch sensing electrode 13. In this embodiment, the reference electrode 14 is disposed on the lower surface of the protective substrate CM, and its material is, for example, a transparent conductive material. A sensing capacitor is formed by a flexible layer FL located between the reference electrode 14 and the touch sensing electrode 13 to sense a third-party pressure Z. The technical features of the reference electrode 14 and its relative relationship with the touch sensing electrode 13 have been described above. Figures 3 to 6D This will be explained in detail in the relevant content and will not be elaborated further.

[0091] Furthermore, other technical features and driving and control methods of the LED touch display devices 1e to 1h can be found in the description of the LED touch display device 1 above, and will not be repeated here.

[0092] In summary, in the LED touch display device of the present invention, the first or second terminal electrode of the light-emitting element is used as the touch sensing electrode of the LED touch display device; or the touch sensing electrode is disposed on the second terminal electrode or between the first terminal electrode and the substrate, and corresponding to the first or second terminal electrode; or a reference electrode is further disposed, and the reference electrode is corresponding to the first or second terminal electrode. Through the above structure, the present invention integrates the process of the touch sensing electrode into the process of a thin-film transistor, and utilizes a self-capacitance touch method, integrating the circuit for controlling the touch function and the circuit for controlling the display function into the same control integrated circuit (IC), thereby reducing the cost of the external touch panel process and the control IC. This results in the LED touch display device of the present invention having the advantages of simplified process and fewer components.

[0093] The above description is merely illustrative and not restrictive. Any equivalent modifications or alterations made without departing from the spirit and scope of this invention should be included in the claims.

Claims

1. A light-emitting diode touch display device, characterized in that, include: A thin-film transistor substrate having a substrate and a transistor disposed on the substrate; A light-emitting element has a first terminal electrode electrically connected to the transistor, a light-emitting layer and a second terminal electrode, the light-emitting layer being sandwiched between the first terminal electrode and the second terminal electrode; Multiple sensing electrode pads are disposed on the second terminal electrode; as well as Patterned electrodes are disposed on the second endpoint electrodes and overlap with the sensing electrode pads.

2. The LED touch display device as described in claim 1, characterized in that, Including: A pixel definition layer is disposed on the first endpoint electrode, exposing a portion of the first endpoint electrode. The first endpoint electrode is electrically connected to the electrode of the transistor through a via, and the via does not overlap with that portion of the first endpoint electrode.

3. The LED touch display device as described in claim 1, characterized in that, Including: A flexible layer is sandwiched between the patterned electrode and the second terminal electrode.

4. The LED touch display device as described in claim 1, characterized in that, It further includes a buffer layer disposed on the substrate, and the transistor disposed on the buffer layer.

5. The LED touch display device as described in claim 1, characterized in that, The transistor includes a channel layer containing low-temperature polycrystalline silicon.

6. The LED touch display device as described in claim 1, characterized in that, Viewed from above, one of the sensing electrode pads has a different area than the other.

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