Display device

A display device includes a display including a plurality of pixels and an input sensor for sensing an input of a user. The display device includes: a driving controller for providing the display with a scan signal and a data signal according to a driving frequency; an input controller for providing a touch driving signal to the input sensor; a horizontal synchronization signal information line connecting the driving controller and the input controller, the horizontal synchronization signal information line transmitting a horizontal synchronization signal therethrough; and a vertical synchronization signal information line connecting the driving controller and the input controller, the vertical synchronization signal information line transmitting a vertical synchronization signal therethrough. Amplitude of the vertical synchronization signal or the horizontal synchronization signal varies according to the driving frequency.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority under 35 U.S.C. § 119(a) to Korean patent application No. 10-2019-0139715 filed on Nov. 4, 2019 in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure generally relates to a display device, and more particularly, to a display device including an input sensor.

2. Related Art

As the information society is developed, requirements of a display device including an input sensor to display an image are increasing in various forms. Recently, various display devices such as a liquid crystal display device, a plasma display device, and an organic light emitting display device have been used.

An input sensor recognizes whether a touch occurs or calculates a touch coordinate by sequentially sensing a plurality of touch sensing electrodes for the purpose of touch sensing and collating the sensed results.

However, signals for driving a display device are coupled to signals for touch sensing, and therefore may act as noise against the input sensor.

Recently, the display device has been driven at a frequency changed for each period or region depending on the kind of an image displayed therein so as to reduce power consumption. Research for reducing the above-described noise, corresponding to a change in frequency of signals for driving the display device, has been conducted.

SUMMARY

Embodiments provide a display device including an input sensor, which is driven at several frequencies and reduces influence of noise on the input sensor.

In accordance with an aspect of the present disclosure, there is provided a display device including a display including a plurality of pixels and an input sensor for sensing an input of a user, the display device including: a driving controller configured to provide the display with a scan signal and a data signal according to a driving frequency; an input controller configured to provide a touch driving signal to the input sensor; a horizontal synchronization signal information line connecting the driving controller and the input controller, the horizontal synchronization signal information line transmitting a horizontal synchronization signal therethrough; and a vertical synchronization signal information line connecting the driving controller and the input controller, the vertical synchronization signal information line transmitting a vertical synchronization signal therethrough, wherein amplitude of the vertical synchronization signal or the horizontal synchronization signal varies according to the driving frequency.

A period in which the touch driving signal is provided may not overlap with a period in which a pulse of the horizontal synchronization signal is provided and a period in which the vertical synchronization signal is provided.

A period in which the touch driving signal is provided may not overlap with a period in which the scan signal is provided and a period in which the data signal is provided.

The driving frequency may have a plurality of driving frequencies. The amplitude of the vertical synchronization signal or the horizontal synchronization signal which varies according to the driving frequency may have a predetermined value.

The driving frequency may vary in a range of 1 Hz to 120 Hz.

The driving controller may include a vertical synchronization signal voltage regulator which alters the amplitude of the vertical synchronization signal, the vertical synchronization signal voltage regulator being electrically connected to one end portion of the vertical synchronization signal information line.

The vertical synchronization signal voltage regulator may include a plurality of resistors connected in series and a plurality of switching elements electrically connected between the one end portion of the vertical synchronization signal information line and nodes disposed between adjacent resistors, respectively.

The input sensor may include a touch driving electrode to which the touch driving signal is provided and a touch sensing electrode to which a touch sensing signal is received. The touch driving electrode and the touch sensing electrode may intersect each other while being insulated from each other.

An initialization voltage signal for allowing the touch driving electrode to be initialized to a predetermined voltage level may be provided before the touch driving signal is provided to the touch driving electrode and before the provision of the touch driving signal is ended.

The touch driving electrode and the touch sensing electrode may be disposed in the same layer.

Any one of the touch driving electrode and the touch sensing electrode may be electrically connected to the other of the touch driving electrode and the touch sensing electrode through a bridge pattern disposed in another layer at a position at which the touch driving electrode and the touch sensing electrode intersect each other.

The amplitude of the vertical synchronization signal may have a first amplitude when the driving frequency is a first frequency and have a second amplitude which is less than the first amplitude when the driving frequency is a second frequency which is less than the first frequency.

Both the amplitudes of the vertical synchronization signal and the horizontal synchronization signal may vary.

The sum of the amplitude of the vertical synchronization signal and the amplitude of the horizontal synchronization signal may have a first amplitude when the driving frequency is a first frequency and have a second amplitude which is less than the first amplitude when the driving frequency is a second frequency which is less than the first frequency.

The display device may further include a frequency information line connecting the driving controller and the input controller, the frequency information line transmitting a binary signal therethrough. The frequency information line may transmit a signal of ‘0’ when the driving frequency is a first frequency, and transmit a signal of ‘1’ when the driving frequency is a second frequency different from the first frequency.

In accordance with another aspect of the present disclosure, there is provided a display device including: a base substrate; a display panel including a TFT circuit layer disposed on the base substrate, the TFT circuit layer including a plurality of transistors; a light emitting device layer disposed on the TFT circuit layer, the light emitting device layer including a light emitting diode electrically connected to at least some of the plurality of transistors, and an encapsulation layer disposed on the light emitting device layer; and an input sensing layer including a first touch conductive layer, a first touch insulating layer and a second touch conductive layer which are sequentially stacked on the encapsulation layer; and a window substrate disposed on the input sensing layer, wherein a period in which a touch driving signal is provided to the input sensing layer does not overlap with a period in which a pulse of the horizontal synchronization signal or a pulse of the vertical synchronization signal is provided to the display panel.

The voltage signal provided to the plurality of transistors may include a scan signal and a data signal.

The input sensing layer may include a touch driving electrode to which the touch driving signal is provided and a touch sensing electrode from which a touch sensing signal is received. The touch driving electrode and the touch sensing electrode may be disposed in the second touch conductive layer.

The touch driving electrode and the touch sensing electrode may be mesh-shaped patterns, and include an opaque conductive material.

The input sensing layer may be patterned directly on the encapsulation layer to form an on-cell type input sensing layer.

DETAILED DESCRIPTION

The effects and characteristics of the present disclosure and a method of achieving the effects and characteristics will be clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed herein but may be implemented in various forms. The embodiments are provided by way of example only so that a person of ordinary skilled in the art can fully understand the features in the present disclosure and the scope thereof. Therefore, the present disclosure can be defined by the scope of the appended claims.

The term “on” that is used to designate that an element or layer is on another element or layer includes both a case where an element or layer is located directly on another element or layer, and a case where an element or layer is located on another element or layer via still another element layer. In the entire description of the present disclosure, the same drawing reference numerals are used for the same elements across various figures.

Although the terms “first,” “second,” and the like are used for describing various components, these components are not confined by these terms. These terms are merely used for distinguishing one component from the other components. Therefore, a first component may be a second component or vice versa according to the technical concepts of the present disclosure.

In this specification, a display device is a device for displaying a moving image or still image or a device for displaying a stereoscopic image, and may be used as a display screen for not only potable electronic devices such as a mobile terminal, a smart phone, a tablet computer, a smart watch, and a navigation system but also various products such as a television, a notebook computer, a monitor, an advertising board, and Internet of things.

Hereinafter, exemplary embodiments will be described with reference to the accompanying drawings. Throughout the drawings, the same reference numerals are given to the same elements.

FIG. 1is a plan view of a display device in accordance with an embodiment of the present disclosure.FIG. 2is a schematic partial sectional view taken along line I-I′ in the display device shown inFIG. 1.

Referring toFIG. 1, the display device1may include an active region AA and a non-active region NAA.

The active region AA is defined as a region for displaying an image. Also, the active region AA may be used as a detection region for detecting an external environment. That is, the active region AA may be used as a region for displaying an image or recognizing an input of a user. The input of the user may include a touch input, fingerprint input, and the like. Hereinafter, the touch input will be described as an example. In an embodiment, the active region AA may have a flat shape. However, the present disclosure is not limited thereto, and at least a partial region of the active region AA may be bent.

The non-active region NAA is defined as a region disposed at the outside of the active region AA and any image is not displayed through the non-active region NAA. Although not separately shown in the drawing, in an embodiment, a speaker module, a camera module, a sensor module, and the like may be disposed in the non-active region NAA. In an embodiment, the sensor module may include at least one of an illuminance sensor, a proximity sensor, an infrared sensor, and an ultrasonic sensor. In an embodiment, like the active region AA, the non-active region NAA may have a flat shape. However, the present disclosure is not limited thereto, and at least a partial region of the non-active region NAA may be bent.

In an exemplary embodiment, the active region AA may have a rectangular shape longer in a lateral direction than in a longitudinal direction on the drawing. The lateral direction and the longitudinal direction are not limited to their terms but may be understood as relative directions intersecting each other. The non-active region NAA may be provided in a rectangular shape having round corners at the outside of the active region AA as described above. The shapes of the active region AA and the non-active region NAA may be defined relative to each other. The shapes of the active region AA and the non-active region NAA are not limited to the above-described shapes. For example, in another embodiment, the active region AA and the non-active region NAA may have various shapes such as an entirely square shape, other polygonal shapes, a circular shape, and an elliptical shape.

Referring toFIG. 2, the display device1may include a first substrate11, a TFT circuit layer12disposed on the first substrate11, a light emitting device layer13disposed on the TFT circuit layer12, an encapsulation layer14disposed on the light emitting device layer13, an input sensing layer15disposed on the encapsulation layer14, and a second substrate16disposed on the input sensing layer15. The stacked structure of the display device1, which is shown inFIG. 2, is merely illustrative. Each layer may have a multi- or single-layered structure. If necessary, another layer may be further added, or some layers may be omitted.

An arrangement structure of the input sensing layer15and the stacked structure of the display device1will be described with reference toFIGS. 3 and 4.

FIG. 3is a layout view schematically illustrating each member of the input sensing layer in the display device in accordance with an embodiment of the present disclosure.FIG. 4is a sectional view of a portion corresponding to line II-II′ shown inFIG. 3in the display device in accordance with an embodiment of the present disclosure. InFIGS. 3 and 4, for convenience of description, an input controller200is illustrated as a block, and a width of the non-active region NAA or a ratio of the non-active region NAA to the active region AA is slightly exaggerated. In addition, a description of the input controller200will be made in detail with reference to drawings fromFIG. 6.

Referring toFIGS. 3 and 4, the display device1includes at least one base substrate301. The display device1may further include a window substrate302disposed to face the base substrate301. However, the present disclosure is not limited thereto, and the window substrate302may be omitted or be replaced with another structure such as a film or layer.

The base substrate301may be a flexible substrate. For example, the base substrate301may be one of a film substrate and a plastic substrate, which include a polymer organic material. For example, the base substrate301may include at least one of polystyrene, polyvinyl alcohol, polymethyl methacrylate, polyethersulfone, polyacrylate, polyetherimide, polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide, polyarylate, polyimide, polycarbonate, triacetate cellulose, and cellulose acetate propionate. Also, the base substrate301may include a fiber reinforced plastic (FRP). However, the present disclosure is not limited thereto, and the base substrate301may be a rigid substrate. The base substrate301may be one of a glass substrate, a quartz substrate, a glass ceramic substrate, and a crystalline glass substrate.

A plurality of light emitting devices, sensing electrodes, and signal lines connected thereto may be disposed on the base substrate301. The active region AA and the non-active region NAA may be distinguished each other by existence of the plurality of light emitting devices on the base substrate301. For example, the plurality of light emitting devices and the sensing electrodes are disposed on the base substrate301in the active region AA and the signal lines are disposed on the base substrate301in the non-active region NAA

The base substrate301may correspond to the first substrate11shown inFIG. 2.

A buffer layer311is disposed on the base substrate301. The buffer layer311functions to planarized a surface of the base substrate301and to prevent penetration of moisture or external air into the display device1, for example, into the TFT circuit layer12and/or the light emitting layer13. The buffer layer311may be an inorganic insulating layer. The buffer layer311may be a single layer or a multi-layer.

A plurality of transistors TR1, TR2, and TR3are disposed on the buffer layer311. The plurality of transistors TR1, TR2, and TR3may be driving transistors. At least one of the transistors TR1, TR2, and TR3may be provided for each pixel. The transistors TR1, TR2, and TR3may be provided in the form of thin film transistors. The transistors TR1, TR2, and TR3may include semiconductor layers ACT1, ACT2, and ACT3, gate electrodes GE1, GE2, and GE3, source electrodes SE1, SE2, and SE3, and drain electrodes DE1, DE2, and DE3, respectively.

In detail, the semiconductor layers ACT1, ACT2, and ACT3are disposed on the buffer layer311. The semiconductor layers ACT1, ACT2, and ACT3may include amorphous silicon, poly-silicon, or an organic semiconductor. In another embodiment, the semiconductor layers ACT1, ACT2, and ACT3may include an oxide semiconductor. Although not shown in the drawings, each of the semiconductor layers ACT1, ACT2, and ACT3may include a channel region, and a source region and a drain region which are disposed at both sides of the channel region and are doped with an impurity.

A first conductive layer which includes the gate electrodes GE1, GE2, and GE3is disposed on a gate insulating layer312. The gate electrodes GE1, GE2, and GE3may be formed of a metallic material having conductivity. For example, the gate electrodes GE1, GE2, and GE3may include molybdenum (Mo), aluminum (Al), copper (Cu), and/or titanium (Ti). Each of the gate electrodes GE1, GE2, and GE3may be a single layer or a multi-layer.

A first interlayer insulating layer313is disposed on the first conductive layer. The first interlayer insulating layer313may be an inorganic layer. The first interlayer insulating layer313may be a single layer or a multi-layer.

A second conductive layer is disposed on the first interlayer insulating layer313. The second conductive layer may include the source electrodes SE1, SE2, and SE3and the drain electrodes DE1, DE2, and DE3. The source electrodes SE1, SE2, and SE3and the drain electrodes DE1, DE2, and DE3are formed of a metallic material having conductivity.

The source electrodes SE1, SE2, and SE3and the drain electrodes DE1, DE2, and DE3may be electrically connected to the source regions and the drain regions of the semiconductor layers ACT1, ACT2, and ACT3through contact holes penetrating the interlayer insulating layer313and the gate insulating layer312, respectively.

Although not shown in the drawings, the display device1may further include a storage capacitor and a switching transistor disposed on the buffer layer311.

A second interlayer insulating layer314is disposed on the second conductive layer. The second interlayer insulating layer314may be an inorganic layer. The second interlayer insulating layer314may be a single layer or a multi-layer.

A third conductive layer is disposed on the second interlayer insulating layer314. The third conductive layer may include a connection electrode319connecting the second conductive layer and a first pixel electrode321which will be described later. The connection electrode319may be electrically connected to each of the drain electrodes DE1, DE2, and DE3(or the source electrodes SE1, SE2, and SE3) through a via hole penetrating the second interlayer insulating layer314. The third conductive layer may be formed of the same material as the second conductive layer, or be formed of one of the materials listed in the second conductive layer or a combination thereof.

In another embodiment, the third conductive layer319and the second interlayer insulating layer314may be omitted. In this case, the second conductive layer and the first pixel electrode321may be electrically connected directly to each other.

A protective layer315is disposed on the third conductive layer. The protective layer315is disposed to cover a pixel circuit including the transistors TR1, TR2, and TR3. The protective layer315may be a passivation layer or a planarization layer. The passivation layer may include SiO2, SiNx, and the like, and the planarization layer may include a material such as acryl or polyimide. The protective layer315may include both the passivation layer and the planarization layer. The passivation layer may be disposed on the third conductive layer, and the planarization layer may be disposed on the passivation layer.

The buffer layer311to the protective layer315may correspond to the TFT circuit layer12shown inFIG. 2.

A plurality of first pixel electrodes321are disposed on the protective layer315. The first pixel electrode321may be an anode electrode of a light emitting diode disposed in each pixel. The light emitting diode may include an organic light emitting diode, a quantum dot light emitting diode, etc. Hereinafter, the organic light emitting diode will be described as an example.

The first pixel electrode321may be electrically connected to the connection electrode319through a via hole penetrating the protective layer315. That is, the first pixel electrode321may be electrically connected to each of the drain electrodes DE1, DE2, and DE3(or the source electrode SE1, SE2, SE3) of the transistors TR1, TR2, and TR3.

The first pixel electrode321may include a material having a high work function. The first pixel electrode321may include Indium Tin Oxide (TIO), Indium Zinc Oxide (IZO), Zinc Oxide (ZnO), Indium Oxide (In2O3), or the like. The exemplified conductive materials have a transparent characteristic while having a relatively high work function. When the display device1is a top-emission display device, the first pixel electrode may further include a reflective material, e.g., silver (Ag), magnesium (Mg), aluminum (Al), platinum (Pt), palladium (Pd), gold (Au), nickel (Ni), neodymium (Nd), iridium (Jr), chromium (Cr), lithium (Li), calcium (Ca) or any mixture thereof, in addition to the exemplified conductive materials. Therefore, the first pixel electrode321may have a single-layered structure made of the exemplified conductive material or the exemplified reflective materials, or have a multi-layered structure in which the exemplified conductive and reflective materials are stacked.

A pixel defining layer325is disposed over the first pixel electrode321. The pixel defining layer325includes an opening exposing at least a portion of the first pixel electrode321, for example, at least a center portion of the pixel electrode321. The pixel defining layer325may include an organic material or an inorganic material. In an embodiment, the pixel defining layer325may be formed of a material including photoresist, polyimide-based resin, acryl-based resin, silicon compound, or the like.

An organic emitting layer322is disposed on the first pixel electrode321exposed by the pixel defining layer325.

A second pixel electrode323is disposed on the organic emitting layer322. The second pixel electrode323may be a common electrode CE disposed throughout the display device1, for example, at least, throughout the active region. Also, the second pixel electrode323may be a cathode electrode of the organic light emitting diode.

The second pixel electrode323may include a material having a low work function. The second pixel electrode323may include Li, Ca, LiF/Ca, LiF/Al, Al, Mg, Ag, Pt, Pd, Ni, Au, Nd, Jr, Cr, BaF, Ba, or any compound or mixture (e.g., a mixture of Ag and Mg) thereof. The second pixel electrode323may further include an auxiliary electrode. The auxiliary electrode may include a layer formed by depositing the low work function material, and a transparent metal oxide, e.g., Indium Tin Oxide (ITO), Iridium Zinc Oxide (IZO), Zinc Oxide (ZnO), Indium Tin Zinc Oxide (ITZO), or the like on the low work function material.

When the display device1is a top-emission display device, a conductive layer having a low work function as the second pixel electrode323may be formed as a thin film, and a transparent conductive layer, e.g., an Indium Tin Oxide (ITO) layer, an Iridium Zinc Oxide (IZO) layer, a Zinc Oxide (ZnO) layer, an Indium Oxide (In2O3) layer, or the like may be stacked on the conductive layer.

The first pixel electrode321, the organic emitting layer322, and the second pixel electrode323, which are described above, may constitute an organic light emitting diode.

The first pixel electrode321to the second pixel electrode323may correspond to the light emitting device layer13shown inFIG. 2.

An encapsulation layer331,332, and333is disposed over the second pixel electrode323. The encapsulation layer may include a first inorganic layer331, an organic layer332, and a second inorganic layer333sequentially disposed on the second pixel electrode323. The first inorganic layer331and the second inorganic layer333may include at least one selected from the group consisting of silicon oxide (SiOx), silicon nitride (SiNx), and silicon oxynitride (SiONx), and the organic layer332may include any one selected from the group consisting of epoxy, acrylate, and urethaneacrylate.

The input sensing layer15is disposed on the encapsulation layer331,332, and333. The input sensing layer15may include an input sensor for sensing a touch input of a user. Hereinafter, the input sensor will be described in detail.

The input sensor may include a plurality of touch sensing electrode TE and RE. The plurality of touch sensing electrode TE and RE may sense a touch, hovering, a gesture, proximity of a user, etc. The touch sensing electrodes TE and RE may be configured in different shapes according to various types such as a resistive type, a capacitive type, an electro-magnetic (EM) type, and an optical type. For example, when the touch sensing electrodes TE and RE are configured as capacitive type touch sensing electrodes, the touch sensing electrodes TE and RE may be configured as self-capacitive type touch sensing electrodes, mutual-capacitive type touch sensing electrodes, or the like.

The plurality of touch sensing electrodes TE and RE may include a transparent conductive material such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), Zinc Oxide (ZnO) or Indium Tin Zinc Oxide (ITZO), or include at least one opaque conductive material selected from the group consisting of molybdenum (Mo), aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), chromium (Cr), calcium (Ca), titanium (Ti), tantalum (Ta), tungsten (W), and copper (Cu).

The input sensor includes a plurality of first touch sensing electrodes RE, a plurality of second touch sensing electrodes TE, and a plurality of touch lines RX and TX connected to the plurality of first touch sensing electrodes RE and the plurality of second touch sensing electrodes TE, respectively. The input sensor may be patterned directly on the encapsulation layer331,332, and333to form an on-cell type input sensor.

The first touch sensing electrode RE may be any one of a touch sensing electrode and a touch driving electrode, and the second touch sensing electrode TE may be the other of the touch sensing electrode and the touch driving electrode. In this embodiment, a case where the first touch sensing electrode RE is the touch sensing electrode and the second touch sensing electrode TE is the touch driving electrode is described as an example.

Although a case where the plurality of first touch sensing electrodes RE include nine touch sensing electrodes RE1to RE9and the plurality of second touch sensing electrodes TE include four touch driving electrodes TE1to TE4is illustrated inFIG. 3, numbers of the first touch sensing electrodes RE and the second touch sensing electrodes TE are not limited to those illustrated inFIG. 3.

The first touch sensing electrode RE may extend in a row direction, and the second touch sensing electrode TE may extend in a column direction intersecting the row direction. The row direction and the column direction are not limited to their terms but may be understood as relative directions intersecting each other.

In an embodiment, a length of the second touch sensing electrode TE in the column direction may be longer than that of the first touch sensing electrode RE in the row direction in general. The display device1may have a shape longer in the column direction than in the row direction. The plurality of first touch sensing electrodes RE may be arranged in the column direction, and the plurality of second touch sensing electrode TE may be arranged in the row direction. In an embodiment, the first touch sensing electrodes RE and the second touch sensing electrodes TE may be provided in a form in which diamond-patterned electrodes are connected.

The first touch sensing electrode RE and the second touch sensing electrode TE may be formed on the same layer. The first touch sensing electrode RE and the second touch sensing electrode TE may be insulated from each other at a portion at which the first touch sensing electrode RE and the second touch sensing electrode TE intersect each other. In order to prevent a short circuit of the first touch sensing electrode RE and the second touch sensing electrode TE, which are disposed in the same layer, one of the first touch sensing electrode RE and the second touch sensing electrode TE may be connected using a bridge pattern BE which is form of a conductive material different from the material forming the first touch sensing electrode RE and the second touch sensing electrode TE.

When the second touch sensing electrodes TE receive a detection signal (or transmission signal) for detecting an external input, the first touch sensing electrode RE may be capacitively coupled to the second touch sensing electrodes TE. When an input means is disposed on a specific second touch sensing electrode TE among the capacitively coupled second touch sensing electrodes TE, a capacitance between the first touch sensing electrode RE and the second touch sensing electrode TE may be changed. The input sensor may calculate coordinate information of the input means by detecting the changed capacitance from the specific second touch sensing electrode TE.

The first touch sensing electrodes RE may be electrically connected to the input controller200by first touch lines RX and the second touch sensing electrodes TE may be electrically connected to the input controller200by second touch lines TX. The input controller200may transmit a touch driving signal having a predetermined voltage level to the second touch sensing electrodes TE and receive a touch sensing signal from the first touch sensing electrode RE, and calculate coordinate information of the input means by detecting a changed capacitance.

The input sensing layer15may include a first touch conductive layer, a first touch insulating layer341disposed on the first touch conductive layer, a second touch conductive layer disposed on the first touch insulating layer341, and a second touch insulating layer342disposed on the second touch conductive layer.

In an embodiment, the first touch conductive layer may be disposed directly on the encapsulation layer331,332, and333, but the present disclosure is not limited thereto. In another embodiment, a base may be included between the encapsulation layer331,332, and333and the first touch conductive layer. The base may be made of plastic such as polyethylene terephthalate (PET), polyimide (PI), polycarbonate (PC), polyethylene (PE), polypropylene (PP), polysulfone (PSF), polymethylmethacrylate (PMMA), triacetylcellulose (TAC), or cycloolefin polymer (COP).

In an embodiment, the above-described bridge pattern BE may be formed of the same material and may be disposed on the same layer as the first touch conductive layer. The first touch conductive layer may include the transparent conductive material or the opaque conductive material, which is described above.

The first touch insulating layer341may include a silicon compound, a metal oxide, and the like. The first touch insulating layer341may include contact holes exposing portions of the first touch conductive layer.

The second touch conductive layer may include the first touch sensing electrodes RE and the second touch sensing electrodes TE. Each of the first touch sensing electrodes RE may be electrically connected to the bridge pattern BE through the contact holes penetrating the first touch insulating layer341.

The second touch insulating layer342may include the same material as the first touch insulating layer341. In another embodiment, the second touch insulating layer342may be omitted.

In an embodiment, the plurality of touch lines TX and RX may be formed at the same time with the first touch conductive layer or the second touch conductive layer. In another embodiment, the plurality of touch lines TX and RX may have a dual line structure in which the plurality of touch lines TX and RX include both the first touch conductive layer and the second touch conductive layer.

The input sensor may sense a touch input of a user in the active region AA.

The first touch to the second touch insulating layer342may correspond to the input sensing layer15shown inFIG. 15. That is, the input sensing layer15shown inFIG. 2may be patterned directly on the encapsulation layer14shown inFIG. 2to form an on-cell type input sensing layer.

The window substrate302may be disposed on the input sensing layer15. The window substrate302may include a transparent substrate including glass, plastic, and the like. The window substrate302may be a sealing substrate or a protective substrate.

The window substrate302may correspond to the second substrate16shown inFIG. 2.

Although not shown in the drawings, an adhesive layer may be included between the input sensing layer15and the window substrate302. The adhesive layer is interposed between the input sensing layer15and the second substrate16to couple the input sensing layer15and the second substrate16to each other. In an example, the adhesive layer may include a film having adhesion, e.g., an Optically Clear Adhesive (OCA). In another example, the adhesive layer may include an Optically Clear Resin (OCR).

FIG. 5is a layout view schematically illustrating a portion of the input sensing layer as a modification of the input sensing layer shown inFIG. 3.

Referring toFIG. 5, first touch sensing electrodes RE and second touch sensing electrode TE in an input sensing layer15_1may be mesh patterns. The mesh pattern may overlap with the pixel defining layer325. In some embodiments, the mesh pattern may not overlap with the first pixel electrode321.

The mesh pattern may include at least one opaque conductive material selected from the group consisting of molybdenum (Mo), aluminum (Al), platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Jr), chromium (Cr), calcium (Ca), titanium (Ti), tantalum (Ta), tungsten (W), and copper (Cu).

Hereinafter, a correlation between a member directly related to display of an image and a member related to an external input from a user will be described. The member directly related to the display of the image may be disposed in the TFT circuit layer12and the light emitting device layer13, and the member related to the external input from the user may be disposed in the input sensing layer15.

FIG. 6is a schematic block diagram of a display device in accordance with the embodiment of the present disclosure.FIG. 7is a block diagram illustrating a relationship between a driving controller and an input controller, which are shown inFIG. 6.FIG. 8is a circuit diagram illustrating a concept of a vertical synchronization signal voltage regulator in the driving controller shown inFIG. 7.

Referring toFIG. 6, the display device includes a display panel10including a plurality of pixels PX, a scan driver20, a data driver30, a timing controller40, and an input controller200.

The display panel10includes the plurality of pixels PX located at intersection portions of a plurality of scan lines SL1to SLn and a plurality of data lines DL1to DLm, to be arranged in a matrix form. Here, m and n are natural numbers. The plurality of pixels PX emit lights, thereby displaying an image in an active region AA.

The plurality of scan lines SL1to SLn may extend in a row direction, and the plurality of data lines DL1to DLm may extend in a column direction. The row direction and the column direction may be reversed.

The scan driver20generates and transfers a scan signal to each pixel PX through a corresponding scan line among the plurality of scan lines SL1to SLn.

The data driver30transfers a data signal to each pixel PX through a corresponding data line among the plurality of data lines DL1to DLm. A data signal supplied to a pixel PX selected by a scan signal whenever the scan signal is supplied to a corresponding scan line among the plurality of scan lines SL1to SLn.

The timing controller40converts a plurality of image signals R, G, and B transferred from the outside into a plurality of image data signals DR, DG, and DB, and transfers the plurality of image data signals DR, DG, and DB to the data driver30. Also, the timing controller40receives a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, and a clock signal MCLK from the outside, to generate control signals for controlling driving of the scan driver20and the data driver30and to transfer the control signals respectively to the scan driver20and the data driver30. The outside may be an application processor.

That is, the timing controller40may generate a scan driving control signal SCS for controlling the scan driver20and a data driving control signal DCS for controlling the data driver30, and transfer the scan driving control signal SCS and the data driving control signal DCS respectively to the scan driver20and the data driver30.

Although not shown in the drawing, each of the plurality of pixels PX is supplied with a first power voltage (not shown) and a second power voltage (not shown). The first power voltage may be a predetermined high level voltage, and the second power voltage may be a voltage lower than the first power voltage.

Each of the plurality of pixels PX emits light with a predetermined luminance according to a driving current flowing through a light emitting diode in response to a data signal transferred through a corresponding data line among the plurality of data lines DL1to DLm.

The first power voltage, the second power voltage, and the like may be supplied from an external voltage source.

The scan driver20, the data driver30, and the timing controller40may be included in a driving controller100for controlling an operation of the display panel10. The driving controller100may be, for example, a driver IC. At least some elements included in the display panel10may be electrically connected directly to the driver IC.

A driving frequency of the driving controller100may vary. In an embodiment, the driving frequency of the driving controller100may vary in a range of 1 Hz to 120 Hz. In an embodiment, the driving controller100may control the display panel10to be driven at three or more frequencies in the above-described range. For example, the display panel10may be selectively driven among 1 Hz, 15 Hz, 30 Hz, 60 Hz, 90 Hz, and 120 Hz, which are exemplary frequencies, according to the kind of an image or a position of the image.

The driving frequency may vary in several forms. In an example, the driving controller100may control the display panel10to be driven at 1 Hz in a partial region of an active region, control the display panel10to be driven at 60 Hz in another partial region of the active region, and control the display panel10to be driven at 120 Hz in the other region of the active region. In another example, the driving controller100may control the display panel10to be driven at 1 Hz during one period, control the display panel10to be driven at 60 Hz during another period, and control the display panel10to be driven at 120 Hz during the other period.

The driving controller100may control the display panel10to be driven at a variable frequency through regulation of the vertical synchronization signal Vsync and the horizontal synchronization signal Hsync in the timing controller40.

The input controller200may receive the vertical synchronization signal Vsync and the horizontal synchronization signal Hsync from the driving controller100, for example, from the timing controller40, and provide a touch driving signal to an input sensor and receive a touch sensing signal from the input sensor. The input controller200may be, for example, a touch IC.

In an embodiment, the input controller200may provide the touch driving signal to the input sensor and receive the touch sensing signal from the input sensor when a scan signal and a data signal are not transmitted to the display panel10.

When the input sensor is formed as an on-cell type input sensor, the scan signal and the data signal may act as noise against the touch driving signal and the touch sensing signal. Therefore, the input controller200may provide the touch driving signal and the touch sensing signal to the input sensor such that a period in which the touch driving signal and the touch sensing signal are provided to the input sensor does not overlap with that in which the scan signal and the data signal are transmitted to the display panel10.

Referring toFIG. 7, the input controller200may receive the vertical synchronization signal Vsync and the horizontal synchronization signal Hsync from the driving controller100, for example, from the timing controller40, to determine a period in which the scan signal and the data signal are transmitted to the input sensor.

In an embodiment, the input controller200and the driving controller100may communicate with each other to exchange signals through a plurality of signal lines. The plurality of signal lines may include a vertical synchronization signal information line Vsync1and a horizontal synchronization signal information line Hsync1. In an embodiment, the plurality of signal lines may be connected in a manner that input/output pins GPIO1and GPIO2disposed at both end portions thereof are respectively coupled to the input controller200and the driving controller100. For example, an input pin GPIO1aof the vertical synchronization signal information line Vsync1may be connected to the driving controller100, and an output pin GPIO1bof the vertical synchronization signal information line Vsync1may be connected to the input controller200. In addition, an input pin GPIO2aof the horizontal synchronization signal information line Hsync1may be connected to the driving controller100, and an output pin GPIO2bof the horizontal synchronization signal information line Hsync1may be connected to the input controller200. Each of the vertical synchronization signal Vsync and the horizontal synchronization signal Hsync, which are provided from the driving controller100to the input controller200, may be a pulse width modulation signal having a predetermined amplitude.

In an embodiment, the amplitude of the vertical synchronization signal Vsync supplied from the driving controller100to the input controller200may vary. Similarly, the amplitude of the horizontal synchronization signal Hsync supplied from the driving controller100to the input controller200may vary.

In an embodiment, the driving controller100may include a vertical synchronization signal voltage regulator110and a horizontal synchronization signal voltage regulator120to alter the amplitude of the vertical synchronization signal Vsync and the amplitude of the horizontal synchronization signal Hsync. The vertical synchronization signal voltage regulator110may be electrically connected to the input pin GPIO1awhich is connected to the vertical synchronization signal information line Vsync1. The horizontal synchronization signal voltage regulator120may be electrically connected to the input pin GPIO2awhich is connected to the horizontal synchronization signal information line Hsync1.

A circuit diagram of the vertical synchronization signal voltage regulator110and a method of regulating the amplitude of the vertical synchronization signal Vsync will be described with reference toFIG. 8. A circuit diagram of the horizontal synchronization signal voltage regulator120and a method of regulating the amplitude of the horizontal synchronization signal Hsync are substantially identical to the circuit diagram of the vertical synchronization signal voltage regulator110and the method of regulating the amplitude of the vertical synchronization signal Vsync, and therefore, overlapping descriptions will be omitted.

The vertical synchronization signal voltage regulator110may include a plurality of switching elements SW11to SW16and a plurality of resistors R11to R16, which are used to vary the amplitude of the vertical synchronization signal Vsync. The amplitude of the vertical synchronization signal Vsync input to the vertical synchronization signal voltage regulator110may be regulated through at least some of the plurality of switching elements SW11to SW16and at least some of the plurality of resistors R11to R16, and the regulated amplitude may be provided to the input pin GPIO1awhich is connected to the vertical synchronization signal information line Vsync1.

In an embodiment, in the vertical synchronization signal voltage regulator110, the plurality of resistors R11to R16having a specific resistance value may be connected in series, and the switching elements SW11and SW16may be connected between a node connecting adjacent resistors and the input pin GPIO1aof the vertical synchronization signal information line Vsync1, respectively. Each of the switching elements SW11to SW16may be provided in the form of a thin film transistor, but the present disclosure is not limited thereto.

For example, in the vertical synchronization signal voltage regulator110, a first resistor R11may be connected between a first node N11and a second node N12, a second resistor R12may be connected between a second node N12and a third node N13, a third resistor R13may be connected between the third node N13and a fourth node N14, a fourth resistor R14may be connected between the fourth node N14and a fifth node N15, a fifth resistor R15may be connected between the fifth node N15and a sixth node N16, and a sixth resistor R16may be connected between the sixth node N16and a seventh node N17. The first node N11may be a node electrically connected to an input terminal to which the vertical synchronization signal Vsync is input, and the seventh node N17may be a node electrically connected to a ground.

A first switching element SW11may be connected between the first node N11and the input pin GPIO1aof the vertical synchronization signal information line Vsync1, a second switching element SW12may be connected between the second node N12and the input pin GPIO1aof the vertical synchronization signal information line Vsync1, a third switching element SW13may be connected between the third node N13and the input pin GPIO1aof the vertical synchronization signal information line Vsync1, a fourth switching element SW14may be connected between the fourth node N14and the input pin GPIO1aof the vertical synchronization signal information line Vsync1, a fifth switching element SW15may be connected between the fifth node N15and the input pin GPIO1aof the vertical synchronization signal information line Vsync1, and a sixth switching element SW16may be connected between the sixth node N16and the input pin GPIO1aof the vertical synchronization signal information line Vsync1.

In an embodiment, each amplitude of a vertical synchronization signal Vsync and/or a horizontal synchronization signal Hsync, corresponding to each driving frequency, may be regulated to have a predetermined amplitude. For example, each amplitude of the corresponding vertical synchronization signal Vsync and/or the corresponding horizontal synchronization signal Hsync may be set to become smaller as the driving frequency becomes smaller, but the present disclosure is not limited thereto.

In an exemplary embodiment, when the driving controller100controls the display to be driven at 120 Hz, the first switching element SW11may be switched on, and the other switching elements SW12to SW16may be switched off. Accordingly, the amplitude of the vertical synchronization signal Vsync provided to the input pin GPIO1aof the vertical synchronization signal information line Vsync1may be regulated to become 1.8 V.

In addition, when the driving controller100controls the display to be driven at 90 Hz, the second switching element SW12may be switched on, and the other switching elements SW11and SW13to SW16may be switched off. Accordingly, the amplitude of the vertical synchronization signal Vsync provided to the input pin GPIO1aof the vertical synchronization signal information line Vsync1may be regulated to become 1.6 V.

In addition, when the driving controller100controls the display to be driven at 60 Hz, the third switching element SW13may be switched on, and the other switching elements SW11, SW12, and SW14to SW16may be switched off. Accordingly, the amplitude of the vertical synchronization signal Vsync provided to the input pin GPIO1aof the vertical synchronization signal information line Vsync1may be regulated to become 1.4 V.

In addition, when the driving controller100controls the display to be driven at 30 Hz, the fourth switching element SW14may be switched on, and the other switching elements SW11to SW13, SW15, and SW16may be switched off. Accordingly, the amplitude of the vertical synchronization signal Vsync provided to the input pin GPIO1aof the vertical synchronization signal information line Vsync1may be regulated to become 1.2 V.

In addition, when the driving controller100controls the display to be driven at 15 Hz, the fifth switching element SW15may be switched on, and the other switching elements SW11to SW14and SW16may be switched off. Accordingly, the amplitude of the vertical synchronization signal Vsync provided to the input pin GPIO1aof the vertical synchronization signal information line Vsync1may be regulated to become 1.0 V.

In addition, when the driving controller100controls the display to be driven at 1 Hz, the sixth switching element SW16may be switched on, and the other switching elements SW11to SW15may be switched off. Accordingly, the amplitude of the vertical synchronization signal Vsync provided to the input pin GPIO1aof the vertical synchronization signal information line Vsync1may be regulated to become 0.8 V.

The driving frequencies and the regulated amplitudes of the vertical synchronization signal Vsync are merely illustrative, and may be set to various frequency levels and amplitudes as needed.

FIG. 9is a timing diagram illustrating a driving method of the input controller in the display device in accordance with the present disclosure.

Referring toFIG. 9, as described above, the input controller200may receive the vertical synchronization signal having various amplitudes from the driving controller100. The input controller200may determine at which frequency the driving controller100controls the display panel10through an amplitude of the vertical synchronization signal Vsync provided from the driving controller100.

For example, when the amplitude of the vertical synchronization Vsync provided to the input controller200is 1.8 V, the input controller200may recognize that the driving controller100controls the display panel10to be driven at 120 Hz. Also, when the amplitude of the vertical synchronization Vsync provided to the input controller200is 1.6 V, the input controller200may recognize that the driving controller100controls the display panel10to be driven at 90 Hz. Also, when the amplitude of the vertical synchronization Vsync provided to the input controller200is 1.4 V, the input controller200may recognize that the driving controller100controls the display panel10to be driven at 60 Hz. Also, when the amplitude of the vertical synchronization Vsync provided to the input controller200is 1.2 V, the input controller200may recognize that the driving controller100controls the display panel10to be driven at 30 Hz. Also, when the amplitude of the vertical synchronization Vsync provided to the input controller200is 1.0 V, the input controller200may recognize that the driving controller100controls the display panel10to be driven at 15 Hz. Also, when the amplitude of the vertical synchronization Vsync provided to the input controller200is 0.8 V, the input controller200may recognize that the driving controller100controls the display panel10to be driven at 1 Hz.

In an embodiment, the input controller200may receive the vertical synchronization signal Vsync at least once per one frame. The input controller200may receive the horizontal synchronization signal Hsync at least equal to or greater than a number of scan lines per one frame.

In an embodiment, a period in which the input controller200provides a touch driving signal to the input sensor (see Tb in Tx shown inFIG. 9) may not overlap with a period in which the driving controller100provides a pulse of the vertical synchronization signal Vsync (a portion of Vsync having lower value) to the input controller200and the display panel10and/or a period in which the driving controller100provides a pulse of the horizontal synchronization signal Hsync (a portion of Hsync having lower value) to the input controller200and the display panel10. For example, a phase (or a rising/falling transition time) of the touch driving signal may differ from phases (or rising/falling transition times) of scan signals or data signals. In another example, the period in which the input controller200provides the touch driving signal to the input sensor may not overlap with a period in which the driving controller100provides scan signals to the display panel10and/or a period in which the driving controller100provides data signals to the display panel10. That is, the period in which the input controller200provides the touch driving signal to the input sensor may not overlap with a period in which the driving controller100provides a voltage signal to the transistors TR1, TR2, and TR3of the pixel PX in the display panel10. The period Tb in which the input controller200provides the touch driving signal to the input sensor may not overlap with a period in which a light emitting state of the organic light emitting diode of the pixel PX is changed thereby display noise is occurred (see Display Noise and Tx, which are shown inFIG. 9). In the drawing, the display noise which deteriorates the touch driving signal from the display panel10is exemplified as noise occurring when a full-white data signal and a full-black data signal are alternately provided to pixel rows arranged in a column direction. The touch driving signal is considerably influenced by the noise when the full-white data signal and the full-black data signal are alternately provided to the pixel rows arranged in the column direction.

Although the driving frequency of the display panel10is altered, the influence of noise which deteriorate the touch driving signal from the display panel10can be minimized.

Meanwhile, the input controller200may initialize voltage levels of the touch sensing electrodes TE and RE. The input controller200may provide an initialization voltage signal CA_RST to each of the touch sensing electrodes TE and RE before the touch driving signal is provided to the touch sensing electrodes TE and RE and before the provision of the touch driving signal is ended. Accordingly, each of the touch sensing electrodes TE and RE may be initialized to a predetermined voltage level before the touch driving signal is provided to the touch sensing electrodes TE and RE and before the provision of the touch driving signal is ended. In an embodiment, a period in which the initialization voltage signal CA_RST is provided may not overlap with the period in which the driving controller100provides the pulse of the vertical synchronization signal Vsync and/or the period in which the driving controller100provides the pulse of the horizontal synchronization signal Hsync. At least a portion of the initialization voltage signal CA_RST may be overlap with the period in which the touch driving signal is provided.

Accordingly, the input sensor can accurately recognize a touch input of a user.

Although a case where the driving controller100varies the amplitude of the vertical synchronization signal Vsync and provides the varied amplitude of the vertical synchronization signal Vsync to the input controller200is described in this embodiment, those skilled in the art will achieve the same purpose by varying the amplitude of the vertical synchronization signal Vsync and providing the varied amplitude of the vertical synchronization signal Vsync to the input controller200.

Next, a display device in accordance with another embodiment will be described. Hereinafter, components identical or similar to those shown inFIGS. 1 to 9are designated by like reference numerals, and overlapping descriptions will be omitted.

FIG. 10is a circuit diagram illustrating a concept of a vertical synchronization signal voltage regulator and a horizontal synchronization signal voltage regulator in a driving controller in a display device in accordance with another embodiment of the present disclosure.

Referring toFIG. 10, the display device in accordance with this embodiment is different from the embodiment shown inFIG. 8, in that the input controller200determines a driving frequency by collecting both the amplitude of the vertical synchronization signal Vsync and the amplitude of the horizontal synchronization signal Hsync.

In an embodiment, the input controller200may determine a driving frequency of the display panel10by using both the amplitude of the vertical synchronization signal Vsync and the amplitude of the horizontal synchronization signal Hsync. For example, the input controller200may determine a driving frequency through the sum of the amplitude of the vertical synchronization signal Vsync and the amplitude of the horizontal synchronization signal Hsync.

In an embodiment, in the horizontal synchronization signal voltage regulator120, a plurality of resistors R21to R26having a specific resistance value may be connected in series, and switching elements SW21to SW26may be connected between a node connecting adjacent resistors and the input pin GPIO2aof the horizontal synchronization signal information line Hsync1, respectively. Each of the switching elements SW21to SW26may be provided in the form of a thin film transistor, but the present disclosure is not limited thereto.

For example, in the horizontal synchronization signal voltage regulator120, a first resistor R21may be connected between a first node N21and a second node N22, a second resistor R22may be connected between the second node N22and a third node N23, a third resistor R23may be connected between the third node N23and a fourth node N24, a fourth resistor R24may be connected between the fourth node N24and a fifth node N25, a fifth resistor R25may be connected between the fifth node N25and a sixth node N26, and a sixth resistor R26may be connected between the sixth node N26and a seventh node N27. The first node N21may be a node electrically connected to an input terminal to which the horizontal synchronization signal Hsync is input, and the seventh node N27may be a node electrically connected to a ground.

A first switching element SW21may be connected between the first node N21and the input pin GPIO2aof the horizontal synchronization signal information line Hsync1, a second switching element SW22may be connected between the second node N22and the input pin GPIO2aof the horizontal synchronization signal information line Hsync1, a third switching element SW23may be connected between the third node N23and the input pin GPIO2aof the horizontal synchronization signal information line Hsync1, a fourth switching element SW24may be connected between the fourth node N24and the input pin GPIO2aof the horizontal synchronization signal information line Hsync1, a fifth switching element SW25may be connected between the fifth node N25and the input pin GPIO2aof the horizontal synchronization signal information line Hsync1, and a sixth switching element SW26may be connected between the sixth node N26and the input pin GPIO2aof the horizontal synchronization signal information line Hsync1.

In an exemplary embodiment, the driving controller100may regulate the amplitude of the vertical synchronization signal Vsync to 1.2 V through the third switching element SW23in the vertical synchronization signal voltage regulator110, and regulate the amplitude of the horizontal synchronization signal Hsync to 0.6 V through the fifth switching element SW25in the horizontal synchronization signal voltage regulator120. The driving controller100may receive, from the input controller200, the vertical synchronization signal Vsync of which amplitude is regulated to 1.2 V and the horizontal synchronization signal Hsync of which amplitude is regulated to 0.6 V, and recognize a driving frequency corresponding to a voltage 1.8 V as the sum of the amplitude of the vertical synchronization signal Vsync and the amplitude of the horizontal synchronization signal Hsync.

FIG. 11is a block diagram illustrating a relationship between a driving controller and an input controller in a display device in accordance with still another embodiment of the present disclosure.

Referring toFIG. 11, the display device in accordance with this embodiment is different from the embodiment shown inFIG. 7, in that the signal lines connecting the driving controller100and the input controller200further include a frequency information line FQ1.

The frequency information line FQ1may be connected in a manner that input/output pins GPIO3aand GPIO3bdisposed at both end portions thereof are respectively coupled to the input controller200and the driving controller100.

The frequency information line FQ1may transmit a binary signal according to a driving frequency of the driving controller100. For example, when the driving frequency is a first frequency, a signal of ‘0’ may be transmitted through the frequency information line FQ1. When the driving frequency is a second frequency different from the first frequency, a signal of ‘1’ may be transmitted through the frequency information line FQ1.

A frequency information line regulator130may regulate whether the signal of ‘0’ or the signal of ‘1’ is to be transmitted through the frequency information line FQ1.

Accordingly, the input controller200can easily recognize two specific frequencies at which the driving controller100controls the display to be driven.

In accordance with the present disclosure, the accuracy of recognition of whether a touch occurs or calculation of a touch coordinate can be increased.