KR102650999B1 - Pressure touch sensor integrated organic light emitting display device - Google Patents

Abstract

An organic light emitting display device integrated with a pressure touch sensor is provided. The pressure touch sensor integrated organic light emitting display device is disposed on a flexible substrate including a thin film transistor, an organic light emitting element connected to the thin film transistor on the flexible substrate, and the bottom of the flexible substrate, and is configured to detect the position of the touch input and measure the intensity of the touch input at the same time. It includes a configured touch sensor unit. The touch sensor unit includes an upper electrode and a lower electrode that faces and is spaced apart from the upper electrode. An organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention provides an organic light emitting display device capable of simultaneously measuring the location of a touch input and the intensity of the touch input.

Description

Pressure touch sensor integrated organic light emitting display device {PRESSURE TOUCH SENSOR INTEGRATED ORGANIC LIGHT EMITTING DISPLAY DEVICE}

The present invention relates to an organic light emitting display device integrated with a pressure touch sensor, and more specifically, to an organic light emitting display device integrated with a pressure touch sensor that can measure not only the position of a touch input but also the intensity of the touch input in response to a touch input. .

A touch screen panel (TSP) is a device that detects a user's touch input, such as a screen touch or gesture, on a display device, including portable display devices such as smartphones and tablet PCs, as well as display devices in public facilities. It is widely used in large display devices such as and smart TVs. These touch panels can be classified into resistive, capacitive, optical, and electromagnetic (EM) types depending on the operation method.

Among various touch panels, the capacitance type is commonly used because it has a fast response speed and a thin thickness. A capacitance-type touch panel calculates the position of a touch input by detecting a change in capacitance between a touch electrode and a finger, or by detecting a change in mutual capacitance according to a touch input between the first and second touch electrodes that cross each other. .

However, this capacitance type touch panel has the limitation of only being able to detect the two-dimensional location of the touch input. In other words, a capacitance-type touch panel can only calculate the location of a touch input by detecting a change in capacitance at the point where the touch input is applied, but cannot measure the intensity of the touch input.

Meanwhile, as electronic devices with touch input functions, such as smartphones and tablet PCs, are widely used, the demand for touch panels that can detect more diverse touch inputs is increasing. Accordingly, research on touch panels that can measure not only the location of the touch input but also the strength of the touch input is actively underway.

Meanwhile, flexible display devices, which are manufactured by forming pixels and wiring on a flexible substrate such as plastic, which is a flexible material, so that images can be displayed even when bent like paper, are attracting attention as next-generation display devices. . In particular, unlike other display devices, flexible organic light emitting display devices using organic light emitting elements do not require a separate light source, so they have the advantage of being lightweight and thin.

The scope of application of flexible organic light emitting displays is becoming more diverse, ranging from computer monitors and TVs to personal portable devices, and research is being conducted on flexible organic light emitting displays that have a large display area but reduced volume and weight. .

The substrate of a flexible organic light emitting display device is made of a thin film to have excellent flexibility. However, thin film-type substrates have the problem of bending and tearing easily. To prevent this, a backplate is placed under the substrate of the flexible organic light emitting display device to prevent bending or tearing of the substrate. The backplate supports the substrate and has a thickness greater than that of the substrate to reinforce the rigidity of the substrate. Meanwhile, when the aforementioned touch panel is attached to the top of the flexible organic light emitting display device, the thickness of the flexible organic light emitting display device becomes thicker.

[Related technical literature]

1. Smartphone (Korean Patent Application No. 10-2015-0105690)

The inventors of the present invention conducted research on a touch panel that can detect both the two-dimensional location of the point where the touch input is applied and the intensity of the touch input. The inventors of the present invention recognized that the method of adding a separate pressure sensor to a display device increases the thickness of the display device, so it is not suitable for thinning the display device and may make it difficult to implement a flexible organic light emitting display device. did. Accordingly, the inventors of the present invention have invented an organic light emitting display device integrated with a pressure touch sensor that can detect the position of a touch input and simultaneously measure the intensity of the touch input with a single structure within a flexible organic light emitting display device.

Accordingly, the problem to be solved by the present invention is to provide an organic light emitting display device integrated with a pressure touch sensor that can simultaneously measure position sensing and pressure sensing below the back plate supporting the substrate in a flexible organic light emitting display device.

Another problem that the present invention aims to solve is a connection with excellent durability without the problem of cracks when one printed circuit board performs the function of transmitting a display driving signal to a thin film transistor and simultaneously applying a touch driving signal to a touch electrode. It provides absence.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

In order to solve the above-described problem, an organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention includes a flexible substrate including a thin film transistor, an organic light emitting element connected to the thin film transistor on the flexible substrate, and disposed below the flexible substrate. and includes a touch sensor unit configured to detect the location of the touch input and simultaneously measure the intensity of the touch input. The touch sensor unit includes an upper electrode and a lower electrode that faces and is spaced apart from the upper electrode. An organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention can simultaneously measure the position of a touch input and the intensity of the touch input, and has thinner organic light emitting display with excellent flexibility by unifying the structure of the touch sensor. A display device may be provided.

Specific details of other embodiments are included in the detailed description and drawings.

The present invention can provide an organic light emitting display device integrated with a pressure touch sensor that can simultaneously measure position sensing and pressure sensing in a flexible organic light emitting display device.

Additionally, the present invention has the effect of improving durability of a connecting member connecting a printed circuit board attached to an organic light emitting display panel and a touch electrode.

The effects according to the present invention are not limited to the contents exemplified above, and further various effects are included in the present specification.

FIG. 1A is a schematic exploded perspective view illustrating an organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention.
FIG. 1B is a schematic cross-sectional view taken along line II-II' of FIG. 1.
FIG. 1C is a schematic cross-sectional view taken along line III-III' in FIG. 1.
2A and 2B are schematic plan views illustrating a touch sensor unit of an organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention.
FIG. 3 is a schematic flow chart for explaining the operation of an organic light emitting display device integrated with a pressure touch sensor according to another embodiment of the present invention.
4A to 4C are schematic diagrams illustrating a method of measuring the location of a touch input and the intensity of the touch input in an organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention.
FIG. 5 is a schematic cross-sectional view illustrating an organic light emitting display device integrated with a pressure touch sensor according to another embodiment of the present invention.

The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and will be implemented in various different forms. The present embodiments only serve to ensure that the disclosure of the present invention is complete and that common knowledge in the technical field to which the present invention pertains is not limited. It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining embodiments of the present invention are illustrative, and the present invention is not limited to the matters shown. Like reference numerals refer to like elements throughout the specification. Additionally, in describing the present invention, if it is determined that a detailed description of related known technologies may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. When 'includes', 'has', 'consists of', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, the plural is included unless specifically stated otherwise.

When interpreting a component, it is interpreted to include the margin of error even if there is no separate explicit description.

In the case of a description of a positional relationship, for example, if the positional relationship between two parts is described as 'on top', 'on the top', 'on the bottom', 'next to', etc., 'immediately' Alternatively, there may be one or more other parts placed between the two parts, unless 'directly' is used.

When an element or layer is referred to as “on” another element or layer, it includes all cases where the other layer or other element is interposed or directly on top of the other element.

Although first, second, etc. are used to describe various elements, these elements are not limited by these terms. These terms are merely used to distinguish one component from another. Accordingly, the first component mentioned below may also be the second component within the technical spirit of the present invention.

Like reference numerals refer to like elements throughout the specification.

The size and thickness of each component shown in the drawings are shown for convenience of explanation, and the present invention is not necessarily limited to the size and thickness of the components shown.

Each feature of the various embodiments of the present invention can be combined or combined with each other, partially or entirely, and various technological interconnections and operations are possible, and each embodiment can be implemented independently of each other or together in a related relationship. It may be possible.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings.

1A to 1C are diagrams for explaining an organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention. Specifically, FIG. 1A is a schematic exploded perspective view illustrating an organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention. FIG. 1B is a schematic cross-sectional view taken along line II-II' of FIG. 1A. FIG. 1C is a schematic cross-sectional view taken along line III-III' of FIG. 1A. Referring to FIG. 1A, the pressure touch sensor integrated organic light emitting display device 100 includes a base substrate 110, a touch sensor unit 120, a back plate 130, a flexible substrate 141, a cover substrate 160, and a connection. Includes member 190.

The flexible substrate 141 serves to support and protect various components of the pressure touch sensor integrated organic light emitting display device 100. The flexible substrate 141 may be made of an insulating material, for example, a plastic material with flexibility. In this case, the flexible substrate 141 may be implemented as a thin plastic film made of a polymer such as polyimide, polyethylene naphthalate (PEN), or polyethylene terephthalate (PET). The flexible substrate 141 may have a thickness of, for example, 5 μm to 50 μm in order to have excellent flexibility.

In this case, the pressure touch sensor integrated organic light emitting display device 100 may be implemented as a flexible organic light emitting display device. The pressure touch sensor integrated organic light emitting display device 100 including a flexible substrate 141 implemented with a thin plastic film is suitable for use in TVs, mobile devices, tablet PCs, monitors, and laptop computers. It can be applied to various display devices, including computers) and vehicle display devices. Alternatively, it may be applied to wearable display devices, foldable display devices, and rollable display devices.

A thin film transistor (TFT) and an organic light emitting device 150 are disposed on the flexible substrate 141. The thin film transistor (TFT) turns on or turns off the organic light emitting device 150, and the organic light emitting device 150 is connected to the pressure touch sensor integrated organic light emitting display device 100. constitutes a pixel. Details about this will be described later with reference to FIG. 1C.

The cover substrate 160 faces the flexible substrate 141 and protects the organic light emitting device 150 and the thin film transistor (TFT) disposed on the flexible substrate 141 from the external environment. The cover substrate 160 may be a colorless transparent glass substrate or a transparent plastic substrate to minimize visibility degradation of the pressure touch sensor integrated organic light emitting display device 100. For example, the cover substrate 160 may be made of a transparent plastic material with flexibility.

According to some embodiments, a polarizing film that prevents reflection of external light may be further disposed on the cover substrate 160. In this case, the visibility of the pressure touch sensor integrated organic light emitting display device 100 may be further improved.

Meanwhile, although not shown in FIG. 1A, an encapsulation layer for sealing the organic light emitting device 150 from the external environment may be disposed instead of the cover substrate 160. The encapsulation layer is configured to encapsulate the organic light emitting device 150. The encapsulation layer is formed of an insulating material. Additionally, the encapsulation layer may be formed as a single-layer structure, or may be formed as a multi-layer structure in which a plurality of insulating layers are stacked. For example, a first encapsulation layer is formed to cover the cathode 153 of the organic light emitting device 150. The first encapsulation layer may be formed of an inorganic insulating material such as silicon nitride (SiNx) to provide a low moisture penetration rate and airtight seal. A second encapsulation layer is formed on the first insulating layer to cover the first encapsulation layer. The second encapsulation layer may be formed of an organic insulating material or silicon oxycarbon (SiOC) to compensate for foreign substances on the first encapsulation layer. A third encapsulation layer is formed to cover the second encapsulation layer. The third encapsulation layer may be formed of an inorganic insulating material with a low moisture penetration rate, such as silicon nitride or aluminum oxide (Al ₂ O ₃ ).

Meanwhile, when describing the thin film transistor (TFT) and the organic light emitting device 150 disposed on the flexible substrate 141, the thin film transistor (TFT) is disposed on the buffer layer 142 on the flexible substrate 141. The buffer layer 142 prevents moisture or impurities from penetrating through the flexible substrate 141 and flattens the top of the flexible substrate 141. However, the buffer layer 142 is not absolutely necessary. Whether or not the buffer layer 142 is formed is determined based on the type of flexible substrate 141 or the type of thin film transistor (TFT).

A thin film transistor (TFT) is formed on the buffer layer 142 and supplies a signal to the organic light emitting device 150. The thin film transistor (TFT) includes an active layer 146, a gate electrode 147, a source electrode 148, and a drain electrode 149. Specifically, the active layer 146 is formed on the buffer layer 142, and a gate insulating layer is formed on the active layer 146 to insulate the active layer 146 and the gate electrode 147. Additionally, a gate electrode 147 is formed on the gate insulating layer to overlap the active layer 146, and an interlayer insulating layer is formed on the gate electrode 147 and the gate insulating layer. A source electrode 148 and a drain electrode 149 are formed on the interlayer insulating layer. The source electrode 148 and the drain electrode 149 are electrically connected to the active layer 146.

Additionally, the active layer 146 may be formed of amorphous silicon (a-Si), polycrystalline silicon (poly-Si), an oxide semiconductor, or an organic semiconductor. When the active layer 146 is formed of an oxide semiconductor, it may be formed of ITO, IZO, Indium Gallium Zinc Oxide (IGZO), or Indium Tin Zinc Oxide (ITZO), but is not limited thereto. When the active layer 146 is formed of IGZO, the ratio of In:Ga:Zn may be 1:2:1. In this case, a Ga-Rich Layer that reduces PBTS may be formed on the upper surface of the IGZO layer in the active layer 146.

In FIG. 1B , for convenience of explanation, only the driving thin film transistor connected to the anode 151 of the organic light emitting device 150 is shown among various thin film transistors that may be included in the pressure touch sensor integrated organic light emitting display device 100. However, the pressure touch sensor integrated organic light emitting display device 100 may further include a switching thin film transistor or a capacitor for driving the organic light emitting element 150. In addition, in this specification, the thin film transistor (TFT) is described as having a coplanar structure, but a thin film transistor (TFT) with an inverted staggered structure may also be used. In addition, Figure 1b shows a structure in which the anode 151 of the organic light emitting device 150 is connected to the drain electrode 149 of a thin film transistor (TFT). However, according to the design, the anode 151 of the organic light emitting device 150 is connected to the drain electrode 149 of the thin film transistor (TFT). It may be connected to the source electrode 148 of a thin film transistor (TFT).

A planarization layer 145 is disposed on the thin film transistor (TFT). The planarization layer 145 is a layer that flattens the upper part of the substrate, and may be formed of an organic insulating material to cover the upper step of the substrate. The planarization layer 145 includes a contact hole for electrical connection to the anode 151 of the organic light emitting device 150.

The organic light emitting device 150 is disposed on the planarization layer 145 and includes an anode 151, an organic layer 152, and a cathode 153. Although only one organic light emitting device 150 is shown in FIG. 1B, a plurality of organic light emitting devices 150 may be arranged to correspond to a plurality of pixel areas of the pressure touch sensor integrated organic light emitting display device 100.

The anode 151 is an electrode that supplies holes to the organic layer 152, and may be made of a transparent conductive material with a high work function. Transparent conductive materials may include, but are not limited to, ITO, IZO, ITZO, etc. As shown in FIG. 1B, when the pressure touch sensor integrated organic light emitting display device 100 is driven in a top emission manner, the anode 151 may further include a reflector. Here, the anode 151 may also be referred to as a pixel electrode.

The cathode 153 is an electrode that supplies electrons to the organic layer 152, and is made of a metal with a relatively low work function, such as silver, titanium (Ti), aluminum, molybdenum (Mo), or silver and magnesium. It may be composed of an alloy (Ag:Mg). Here, the cathode 153 may also be referred to as a common electrode. When the cathode 153 is made of an alloy of silver and magnesium, the resistance of the cathode 153 can be lowered by increasing the silver content compared to the magnesium content. At this time, in order to prevent silver from oxidizing and lowering resistance, a Ytterbium (YB) layer may be disposed on the top, bottom, or above and below the Ag:Mg layer, respectively.

An organic layer 152 is disposed between the anode 151 and the cathode 153. The organic layer 152 includes an organic light emitting layer. The organic emission layer has a patterned emission layer structure, as shown in FIG. 1B. In this case, light-emitting layers emitting different colors are formed separately for each pixel. For example, a red organic light-emitting layer for emitting red light, a green organic light-emitting layer for emitting green light, and a blue organic light-emitting layer for emitting blue light are respectively a red sub-pixel, a green sub-pixel, and a blue sub-pixel. can be formed separately. In this case, the red sub-pixel, green sub-pixel, and blue sub-pixel may constitute one pixel. In each of the red organic emission layer, the green organic emission layer, and the blue organic emission layer, holes and electrons supplied through the anode 151 and the cathode 153 combine with each other to emit light. Each organic light emitting layer may be deposited in a pattern using a mask with openings for each sub-pixel, for example, a fine metal mask (FMM). However, the present invention is not limited to this, and the organic light emitting layer may be commonly formed in all sub-pixels on the flexible substrate 141. In this case, the organic light-emitting layer may be made of a material that emits white light, and a color filter may be arranged to correspond to the area where the organic light-emitting layer emits light.

In addition to the organic light emitting layer, the organic layer 152 may further include organic layers 152 such as an injecting layer and a transporting layer to improve the light emitting efficiency of the organic light emitting device 150. At least some of these organic layers 152 may have a common structure that is commonly disposed in a plurality of sub-pixels to take advantage of the manufacturing process.

Here, the organic layer 152 having a common structure may be formed using a common mask in which all sub-pixels are open, and may be stacked with the same structure on all sub-pixels without a pattern for each sub-pixel. That is, the organic layer 152 having a common structure is arranged to be connected or extended from one sub-pixel to a neighboring sub-pixel without a break, and is shared by a plurality of sub-pixels.

For example, in addition to the organic light emitting layer, a hole injection layer or a hole transport layer may be further disposed between the anode 151 and the cathode 153 to facilitate the movement of holes. The hole injection layer or the hole transport layer may have a common structure that is commonly disposed in a plurality of sub-pixels. In some embodiments, the hole transport layer may be composed of a p-type hole transport layer doped with a p-type dopant.

Additionally, the bank layer 154 may define a sub-pixel and exposes a portion of the upper surface of the anode 151. Specifically, the bank layer 154 may be disposed to cover the edge of the anode 151. The bank layer 154 is made of an insulating material to insulate the anodes 151 of adjacent sub-pixels from each other. According to some embodiments, the bank layer 154 may be composed of a black bank with a high light absorption rate to prevent color mixing between adjacent sub-pixels.

Meanwhile, a filling member 165 is disposed to fill the space between the cover substrate 160 and the organic light emitting device 150. The filling member 165 may be formed of a transparent desiccant to prevent moisture from penetrating into the organic light emitting device 150.

A back-plate 130 is disposed on the lower part of the flexible substrate 141. The back plate 130 supports the flexible substrate 141 so that the substrate is not easily bent or torn. As mentioned above, the flexible substrate 141 may be in the form of a thin film, and in this case, the thickness of the substrate is very thin, so it can be easily bent or torn. The back plate 130 supplements the rigidity of the flexible substrate 141 by supporting a thin film-type substrate.

The back plate 130 is made of polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyethylene ether phthalate, polycarbonate, polyarylate, and polyether. It may be formed of one or more materials selected from polyether imide, polyether sulfonate, polyimide, or polyacrylate, but is not limited thereto.

The touch sensor unit 120 is disposed below the back plate 130 and is configured to detect the location of the touch input in response to the user's touch and at the same time measure the intensity of the touch input. The touch sensor unit 120 includes a lower electrode 121, an upper electrode 122, a spacer layer 123, and an air gap 124.

The upper electrode 122 and the lower electrode 121 may be formed of a metal with excellent conductivity. In particular, in the touch sensor-integrated organic light emitting display device according to an embodiment of the present invention, the touch sensor unit 120 that recognizes a touch is disposed below the organic light emitting element 150, and therefore does not necessarily have to be made of a transparent material. . That is, in order to improve sensing performance, it is desirable to include any one of metals with excellent conductivity such as silver, aluminum, and copper.

The upper electrode 122 and the lower electrode 121 are disposed to face each other and are spaced apart from each other by a certain distance. That is, a spaced space occurs between the upper electrode 122 and the lower electrode 121. In order to provide a space between the upper electrode 122 and the lower electrode 121, a spacer layer 123 is disposed between the upper electrode 122 and the lower electrode 121.

The spacer layer 123 is configured to space the upper electrode 122 and the lower electrode 121 apart. For example, the spacer layer 123 may be formed at the edges of the upper electrode 122 and the lower electrode 121. The two electrodes are bonded through the spacer layer 123 at the edge areas of each of the upper electrode 122 and the lower electrode 121, but in the remaining inner area, the lower electrodes 121 of the upper electrode 122 are spaced apart by a predetermined distance. do. For example, the spacer layer 123 may be disposed in the form of a double-sided adhesive tape bonded to one side of the upper electrode 122 and the lower electrode 121.

The space separated by the spacer layer 123 may be implemented as an air gap 124. Due to the pressure caused by the user's touch input, the upper electrode 122 is bent into the air gap 124, thereby reducing the distance between the upper electrode 122 and the lower electrode 121. Due to this, by detecting the change in mutual capacitance between the upper electrode 122 and the lower electrode 121, it is possible to measure whether the user has touched a touch, the location of the touch, and the intensity of the touch pressure. Details of detecting the user's touch input through the touch sensor unit 120 will be described later with reference to FIG. 3.

The touch controller provides a touch driving signal to the upper electrode 122 and receives a touch sensing signal from the lower electrode 121. The touch controller detects the position and intensity of the touch input by analyzing changes in the waveform and amplitude of the touch driving signal and the touch sensing signal. Details about this will be described later with reference to FIG. 3.

The touch controller is connected to the first printed circuit board 171 and the second printed circuit board 172.

More specifically, referring to FIGS. 1A and 1B , the first printed circuit board 171 is connected to the upper electrode 122 and is disposed on the flexible substrate 141. Additionally, the second printed circuit board 172 is connected to the lower electrode 121 and is disposed on the base board 110. At this time, the first printed circuit board 171 is in contact with the first pad portion 181 disposed on the flexible substrate 141, and the second printed circuit board 172 is in contact with the first pad portion 181 disposed on the base substrate 110. 2 It is in contact with the pad portion 182.

Meanwhile, the first printed circuit board 171 and the second printed circuit board 172 are connected to the touch controller. The touch controller is disposed on the system board of the pressure touch sensor integrated organic light emitting display device 100. However, it is not limited to this, and the touch controller is disposed on the first printed circuit board 171 or the second printed circuit board 172 in a COF (Chip On Film) form, or on the flexible board 141 in a COF (COG) form. It can be placed directly in the form of Chip on Glass.

At this time, the first printed circuit board 171 is configured to transmit the display driving signal to the thin film transistor formed on the flexible board 141. In the conventional case, a printed circuit board for transmitting a display driving signal and a printed circuit board for transmitting a touch driving signal were formed separately, which had the problem of increasing the thickness of the organic light emitting display device and the size of the bezel area. . However, there is an advantage in reducing the non-display area by configuring the first printed circuit board 171 to transmit the display driving signal and the touch driving signal simultaneously.

Meanwhile, as described above, the connecting member 190 is connected to the flexible substrate 141 so that the first printed circuit board 171 disposed on the flexible substrate 141 is connected to the upper electrode 122 of the touch sensor unit 120. 141) and the back plate 130. Specifically, the connecting member 190 is configured to electrically connect the first printed circuit board 171 and the upper electrode 122. Because of this, the connection member 190 is configured to transmit a touch drive signal from the touch controller to the upper electrode 122. More specifically, the connecting member 190 contacts the first pad portion 181 connected to the first printed circuit board 171 and contacts the upper electrode 122.

The connecting member 190 may be formed by printing metal ink in a dot shape and then hardening it. For example, the connecting member 190 may be made of silver (Ag). Since silver has low sheet resistance, it is easy to electrically connect the first pad portion 181 and the upper electrode 122.

Meanwhile, the connecting member 190 may further include a silicon-based polymer. The connection member 190 is disposed in contact with several components, such as the first pad, flexible substrate 141, back plate 130, and upper electrode 122, and is positioned in contact with various components such as the first pad, flexible substrate 141, and upper electrode 122. Cracks may occur in the connecting member 190. However, when the connecting member 190 includes a silicone-based polymer, fracture and cracks of the connecting member 190 can be minimized due to the properties of the silicone-based polymer, and the connecting member 190 can be easily formed even on an irregular surface. You can.

Hereinafter, a method for recognizing a touch input and a touch sensor unit of an organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention will be described in detail. 2A and 2B are schematic plan views illustrating a touch sensor unit of an organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention. FIG. 3 is a schematic flow chart for explaining the operation of an organic light emitting display device integrated with a pressure touch sensor according to another embodiment of the present invention. 4A to 4C are schematic diagrams illustrating a method of measuring the location of a touch input and the intensity of the touch input in an organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention.

First, the shapes of the upper and lower electrodes will be described with reference to FIGS. 2A and 2B. Figure 2a is a top view of the upper electrode, and Figure 2b is a top view of the lower electrode.

Referring to FIG. 2A, the upper electrode 122 is composed of a single layer. The upper electrode 122 may be formed as a single layer on one surface of the backplate 130. The upper electrode 122 is electrically connected to the first printed circuit board 171 through a connecting member 190. The upper electrode 122 receives a touch driving signal from the first printed circuit board 171.

Referring to FIG. 2B, the lower electrode 121 is composed of a plurality of pattern electrodes. The lower electrode 121 may be formed in a plurality of pattern shapes on the base substrate 110. Specifically, the lower electrode 121 includes a lower electrode substrate 121a, a plurality of touch blocks 121b, and a plurality of wires 121c.

The lower electrode substrate 121a is a substrate on which a plurality of touch blocks 121b are disposed, and may be an independent substrate or an adjacent substrate such as the base substrate 110 disposed below the lower electrode.

The plurality of touch blocks 121b may be configured in various shapes such as polygonal, circular, or oval. The waveform and amplitude of the touch sensing signal of each of the plurality of touch blocks 121b are changed by the user's touch. This change in the touch sensing signal is transmitted to the second printed circuit board 172 through the plurality of wires 121c.

Hereinafter, a method in which the pressure touch sensor integrated organic light emitting display device 100 according to an embodiment of the present invention detects the position of a touch input and simultaneously measures the intensity of the touch input will be described.

Referring to FIG. 3, a touch driving signal TD is applied from the first printed circuit board to the upper electrode (S310). The touch driving signal TD applied to the upper electrode may be a pulse signal with a constant phase.

Next, a touch sensing signal of the lower electrode is received from the second printed circuit board (320). Before the user makes a touch input, each of the plurality of touch blocks constituting the lower electrode has the same touch sensing signal (TS _Ref ). Referring to FIG. 4A, when a user makes a touch input, pressure is applied to the upper electrode, thereby reducing the distance (d ₂ ) between the upper electrode at the position where the touch was input and the touch block of the corresponding lower electrode. Accordingly, the effective capacitance between the touch blocks of the upper electrode and the lower electrode increases, and the touch sensing signal value (FS _a ) of the corresponding touch block changes.

Accordingly, the amount of change in the touch sensing signal is measured (S330).

Afterwards, the amount of change in the measured touch sensing signal is compared with a predetermined touch recognition threshold (S340). If the measured change amount of the touch sensing signal is less than the touch recognition threshold value, it is determined that the touch input has not been made (S351). However, if the measured change amount of the touch sensing signal is greater than or equal to the touch recognition threshold value, it is determined that a touch input has occurred (S361). At this time, it is determined that a touch has been applied to the touch block that transmitted the change in the measured touch signal. That is, the location of the touch input is determined.

After determining the location of the touch input, the intensity of the touch input pressure is measured. That is, the touch input intensity can be calculated according to the size or size of the measured change in the touch sensing signal (S362). Referring to FIG. 4B, a touch is input with greater pressure compared to FIG. 4A, so that the distance (d ₃ ) between the upper electrode and the touch block of the corresponding lower electrode is further reduced. In this case, the amount of change in the measured touch sensing signal (FS _b ) is greater than the amount of change in the touch sensing signal (FS _a ) measured in FIG. 4A. Additionally, referring to FIG. 4C , a touch was input with greater pressure compared to FIGS. 4A and 4B , and the amount of change in the touch sensing signal (FS _c ) measured at this time also significantly increased. Therefore, the intensity of the touch input can be calculated based on the amount of change in the touch sensing signal.

Based on this, the intensity of each pressure touch is sensed (S363).

FIG. 5 is a schematic cross-sectional view illustrating an organic light emitting display device integrated with a pressure touch sensor according to another embodiment of the present invention. Compared to the pressure touch sensor integrated organic light emitting display device 100 shown in FIGS. 1A and 1B, the pressure touch sensor integrated organic light emitting display device 500 according to another embodiment of the present invention shown in FIG. 5 has a touch sensor. Since the configuration of the unit 520 is substantially the same except for differences, duplicate description thereof will be omitted.

The touch sensor unit 520 includes a lower electrode 121, an upper electrode 122, and an elastic member 525.

The elastic member 525 is disposed between the lower electrode 121 and the upper electrode 122. The elastic member 525 is between the lower electrode 121 and the upper electrode 122 and insulates the lower electrode 121 and the lower electrode 122 from each other. When a touch input is applied to the pressure touch sensor integrated organic light emitting display device 500, the elastic member 525 is compressed in response to the touch input, and when the touch input is released, the elastic member 525 is restored to its original thickness. The elastic member 525 has an appropriate modulus so that compression and restoration can be performed smoothly.

The elastic member 525 may be formed of an elastomer that can be smoothly compressed and restored in response to a touch input. For example, the elastic member 525 is polyolefin-based, PVC (polyvinyl chloride)-based, polystyrene-based, polyester-based, polyurethane-based, polyamide-based, etc. It can be formed of the same thermoplastic elastomer (TPE). However, the constituent material of the elastic member 525 is not limited to this, and the elastic member 525 may be composed of various materials having elastic force. The elastic member 525 may be formed as a single-layer structure including the elastic body or a multi-layer structure including a film other than the elastic body. For example, the elastic member 525 may be formed in a multi-layer structure of an elastic body and thin glass. Since thin film glass has a low moisture penetration rate, it can function as a moisture penetration suppression layer that prevents moisture from penetrating into the flexible substrate from the bottom of the flexible substrate.

The elastic member 525 has an appropriate thickness to facilitate compression and restoration in response to a touch input. For example, the elastic member can be formed to a thickness of 50 μm to 300 μm. When the elastic member 525 has the above thickness, the pressure touch sensor integrated organic light emitting display device can be implemented as a flexible organic light emitting display device that maintains appropriate rigidity.

The organic light emitting display device with integrated pressure touch sensor according to an embodiment of the present invention changes the structure to simultaneously measure position sensing and pressure sensing at the bottom of the backplate supporting the substrate in the flexible organic light emitting display device, thereby detecting the touch input. The position and intensity of touch input can be measured simultaneously, and by unifying the structure of the touch sensor, thinness and excellent flexibility can be realized.

An organic light emitting display device integrated with a pressure touch sensor according to embodiments of the present invention may be described as follows.

An organic light emitting display device integrated with a pressure touch sensor according to an embodiment of the present invention includes a flexible substrate including a thin film transistor, an organic light emitting element connected to the thin film transistor on the flexible substrate, and disposed below the flexible substrate, and detects the position of the touch input. At the same time, it includes a touch sensor unit configured to measure the intensity of a touch input, and the touch sensor unit includes an upper electrode and a lower electrode that is spaced apart from the upper electrode and faces the upper electrode.

The touch sensor unit may further include a spacer layer to form an air gap between the upper electrode and the lower electrode.

The touch sensor unit may further include an elastic member between the upper electrode and the lower electrode.

The thickness of the elastic member may be 50 to 300 um.

The upper electrode is disposed on a flexible substrate, and the upper electrode may include any one of silver, aluminum, and copper.

The upper electrode may be composed of a single layer.

The lower electrode may be composed of a plurality of pattern electrodes.

It may further include a first printed circuit board configured to transmit a touch driving signal to the upper electrode and a second printed circuit board configured to receive a touch sensing signal from the lower electrode.

It may further include a connecting member configured to electrically connect the first printed circuit board and the upper electrode, and the connecting member may be arranged to surround the sides of the flexible substrate and the backplate.

The connecting member may include silver (Ag).

The connecting member may further include a silicone-based polymer.

The first printed circuit board may be configured to transmit a display driving signal to a thin film transistor.

Although embodiments of the present invention have been described in more detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various modifications may be made without departing from the technical spirit of the present invention. . Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted in accordance with the claims below, and all technical ideas within the equivalent scope should be construed as being included in the scope of rights of the present invention.

100: Pressure touch sensor integrated organic light emitting display device
110: base substrate
120: Touch sensor unit
121: lower substrate
122: upper substrate
123: Spacer layer
124: air gap
130: backplate
141: Flexible substrate
150: Organic light emitting device
160: cover substrate
171: first printed circuit board
172: first printed circuit board
181: first pad portion
182: Second pad portion
190: Connection member

Claims (12)

A flexible substrate including a thin film transistor;
an organic light emitting device connected to the thin film transistor on the flexible substrate;
a touch sensor unit disposed below the flexible substrate and configured to detect the position of a touch input and measure the intensity of the touch input at the same time; and
Comprising a plurality of printed circuit boards connected to the touch sensor unit,
The touch sensor unit includes an upper electrode and a lower electrode facing and spaced apart from the upper electrode,
The plurality of printed circuit boards include a first printed circuit board configured to transmit a touch driving signal to the upper electrode and a second printed circuit board configured to receive a touch sensing signal from the lower electrode. display device. According to claim 1,
The touch sensor unit further includes a spacer layer to form an air gap between the upper electrode and the lower electrode. According to claim 1,
The touch sensor unit further includes an elastic member between the upper electrode and the lower electrode. According to clause 3,
An organic light emitting display device with a pressure touch sensor integrated, wherein the elastic member has a thickness of 50 to 300 um. According to claim 1,
The upper electrode is disposed on the flexible substrate,
An organic light emitting display device integrated with a pressure touch sensor, wherein the upper electrode includes any one of silver, aluminum, and copper. According to clause 5,
An organic light emitting display device integrated with a pressure touch sensor, wherein the upper electrode is composed of a single layer. According to claim 1,
An organic light emitting display device integrated with a pressure touch sensor, wherein the lower electrode is composed of a plurality of pattern electrodes. delete According to claim 1,
Further comprising a connecting member configured to electrically connect the first printed circuit board and the upper electrode,
The connection member is disposed to surround sides of the flexible substrate and the backplate. According to clause 9,
An organic light emitting display device integrated with a pressure touch sensor, wherein the connecting member includes silver (Ag). According to claim 10,
The connection member further includes a silicon-based polymer. According to claim 1,
The first printed circuit board is configured to transmit a display driving signal to the thin film transistor.

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