Method for testing display device and display device

Abstract

A method of testing a display device using a touch sensor and a touch integrated circuit, and a display device are provided. The touch sensor includes driving electrode lines and detection electrode lines, and the touch integrated circuit includes a signal driving unit and a signal detection unit. The method includes sensing a first mutual capacitance of a predetermined test coordinate by applying a first driving signal to the driving electrode lines and receiving a detection signal from the detection electrode lines; sensing a second mutual capacitance of a predetermined test coordinate by applying a second driving signal to the driving electrode line and receiving a detection signal from the detection electrode line; and determining whether a touch operation is performed based on a difference between the first mutual capacitance and the second mutual capacitance.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is based on and claims the benefit of priority from Korean Patent Application No. 10-2023-0117937 filed in the Korean Intellectual Property Office on September 5, 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] One or more embodiments relate to a method for testing a display device and a display device. More specifically, one or more embodiments relate to a method for testing a display device, which determines whether a touch detection device operates normally without directly touching a contact object, and a display device, which uses a touch sensor and a touch integrated circuit. Background Art

[0004] Recently, the use of display devices has been diversified. As display devices have become thinner and lighter, their use range has expanded.

[0005] The display device may include a touch detection device as an input device. The touch detection device may include a touch sensor provided on the front side of the display device, and a touch integrated circuit for driving the touch sensor and sensing a touch.

[0006] Touch detection methods of known touch detection devices include electromagnetic induction, pressure detection, capacitance, etc. In a capacitive touch detection device, when a touch sensor contacts a contact object such as a human finger or a stylus, a touch integrated circuit detects changes in capacitance of electrodes included in the touch sensor to determine whether a touch input has been received and the position of the touch. Summary of the invention

[0007] When testing whether a touch detection device of a display device operates normally by directly touching the display device with a finger, the accuracy of the test may vary depending on the size of the inspector's finger, the degree of adhesion, etc. In one aspect, the present disclosure relates to a method for testing a display device by using a touch sensor and a touch integrated circuit to determine whether the touch detection device operates normally without directly touching a contact object, and a display device. However, one or more embodiments are merely examples, and the scope of the present disclosure is not limited thereto.

[0008] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the embodiments of the disclosure.

[0009] According to one or more embodiments, a method for testing a display device by using a touch sensor and a touch integrated circuit is provided, wherein the touch sensor includes a driving electrode line and a detection electrode line, and wherein the touch integrated circuit includes a signal driving unit and a signal detection unit, the method may include: sensing a first mutual capacitance of a predetermined test coordinate by applying a first driving signal to the driving electrode line and receiving a detection signal from the detection electrode line; sensing a second mutual capacitance of a predetermined test coordinate by applying a second driving signal to the driving electrode line and receiving a detection signal from the detection electrode line; and determining whether a touch operation is performed based on a difference between the first mutual capacitance and the second mutual capacitance.

[0010] The second driving signal may be selected such that a second mutual capacitance according to the second driving signal has a value corresponding to a mutual capacitance corresponding to a direct touch of the contact object.

[0011] The signal driving unit may include: a first switch and a second switch which are selectively turned on and connect the signal driving unit and the driving electrode line to each other; and a test resistor connected to the driving electrode line through the second switch.

[0012] When the first switch is turned on, the driving signal generated by the signal driving unit may be transmitted to the driving electrode line as a first driving signal, and when the second switch is turned on, the driving signal may be transmitted to the driving electrode line as a second driving signal.

[0013] The size of the test resistor may be selected so that the second mutual capacitance when the second switch is turned on has a value corresponding to the mutual capacitance when the contact object directly contacts the display device.

[0014] The test resistance may have a range of about 800Ω to about 1200Ω.

[0015] The signal driving unit may include a charge pump configured to boost an input voltage and output the boosted voltage, and the first driving signal and the second driving signal may be adjusted according to a boosting degree of the charge pump.

[0016] The second voltage corresponding to the second driving signal may be lower than the first voltage corresponding to the first driving signal.

[0017] Each of the first voltage and the second voltage may have a range of about 3V to about 6V.

[0018] The driving electrode lines may include driving electrodes arranged in a first direction and first connecting electrodes connecting driving electrodes adjacent to each other in the first direction, and the detecting electrode lines may include detecting electrodes arranged in a second direction intersecting the first direction and second connecting electrodes connecting detecting electrodes adjacent to each other in the second direction.

[0019] Each of the first mutual capacitance and the second mutual capacitance may be a capacitance between one of the first connection electrodes and one of the second connection electrodes, the one first connection electrode and the one second connection electrode together defining a predetermined test coordinate.

[0020] The driving electrode lines may include a plurality of driving electrode lines arranged apart from each other in the second direction, and the detecting electrode lines may include a plurality of detecting electrode lines arranged apart from each other in the first direction.

[0021] According to one or more embodiments, a display device includes: a touch sensor including a driving electrode line and a detection electrode line; a touch integrated circuit including a signal driving unit and a signal detection unit, wherein the signal driving unit applies a driving signal to the driving electrode line, and the signal detection unit receives a detection signal from the detection electrode line; a control unit that determines whether a touch is input by a change in mutual capacitance between the driving electrode line and the detection electrode line; a plurality of switches configured to selectively turn on and connect the signal driving unit to the driving electrode line according to a control signal of the control unit; and a test resistor connected to the driving electrode line through at least one of the plurality of switches, wherein the size of the test resistor is selected so that the mutual capacitance generated when the test resistor is connected to the driving electrode line has a value corresponding to the mutual capacitance generated when the contact object directly contacts the display device.

[0022] A plurality of switches may be connected in parallel with each other.

[0023] The test resistance may have a range of about 800Ω to about 1200Ω.

[0024] The plurality of switches may include a first switch and a second switch, the second switch connecting the test resistor to the driving electrode line.

[0025] The driving electrode line may include driving electrode units arranged in a first direction and first connecting electrodes connecting driving electrode units adjacent to each other in the first direction, and the detecting electrode line may include detecting electrode units arranged in a second direction intersecting the first direction and second connecting electrodes connecting detecting electrode units adjacent to each other in the second direction.

[0026] In a plan view, each of the first connection electrodes may have at least a portion overlapping one of the second connection electrodes.

[0027] The driving electrode lines may include a plurality of driving electrode lines separated from each other in the second direction, and the plurality of driving electrode lines may be respectively connected to the plurality of switches.

[0028] The display device may further include a driving signal line connecting the signal driving unit and the driving electrode line to each other, and a detection signal line connecting the signal detection unit and the detection electrode line to each other.

[0029] These and / or other aspects will become apparent and more readily understood from the claims, the accompanying drawings and the following description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and other aspects, features and advantages of certain embodiments of the present disclosure will become more apparent from the following description in conjunction with the accompanying drawings, in which:

[0031] Figure 1 is a plan view schematically showing a display device according to an embodiment;

[0032] Figure 2 is a cross-sectional view schematically showing a display device according to one or more embodiments;

[0033] Figure 3 is a block diagram schematically showing a display device according to an embodiment;

[0034] Figure 4 is an equivalent circuit diagram of a pixel included in a display device according to an embodiment;

[0035] Figure 5 It is schematically shown Figure 1 A cross-sectional view of the display device shown in taken along line II';

[0036] Figure 6 is a diagram schematically showing a touch detection device included in a display device according to an embodiment;

[0037] Fig. 7A , Figure 7B and Figure 7C is a plan view schematically showing a portion of a touch detection area;

[0038] Figure 8 is a diagram for describing a sensing principle of a display device according to an embodiment;

[0039] Fig. 9 is a diagram for describing a display device and a sensing principle of the display device according to an embodiment;

[0040] Fig. 10A and Fig. 10B is a diagram for describing a method of testing a display device according to an embodiment;

[0041] Fig.11 is a diagram for describing a display device and a method of testing the display device according to an embodiment;

[0042] Fig. 12A and Fig. 12Bis a diagram for describing a test resistor of a display device and a method of testing the display device according to an embodiment;

[0043] Fig.13 is a diagram for describing a sensing principle of a display device according to an embodiment; and

[0044] Fig.14A and Fig. 14B 2 is a diagram for describing a display device and a method of testing the display device according to an embodiment. DETAILED DESCRIPTION

[0045] Reference will now be made in detail to embodiments, examples of which are shown in the accompanying drawings, in which the same reference numerals represent the same elements throughout. In this regard, embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Therefore, embodiments are described below only by reference to the accompanying drawings to explain various aspects of this specification. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. Throughout this disclosure, the expression "at least one of a, b, and c" means only a, only b, only c, both a and b, both a and c, both b and c, all a, b, and c, or variations thereof.

[0046] Since the present disclosure allows various changes and multiple embodiments, certain embodiments will be shown in the drawings and described in detail in the written description. Hereinafter, the effects and features of the present disclosure and methods for implementing them will be more fully described with reference to the drawings, in which embodiments of the present disclosure are shown. However, the present disclosure can be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0047] Hereinafter, embodiments will be described with reference to the accompanying drawings, wherein like reference numerals denote like elements throughout and repeated descriptions thereof will be omitted.

[0048] In the following embodiments, terms such as "first" and "second" are used herein only to describe various elements, but these elements are not limited by these terms. These terms are used only for the purpose of distinguishing one element from another element.

[0049] In the following embodiments, an expression used in the singular includes an expression in the plural unless it has an apparently different meaning in the context.

[0050] Furthermore, it will be understood that the terms “comprising,” “including,” and “having” used herein specify the presence of stated features or elements, but do not preclude the presence or addition of one or more other features or elements.

[0051] It will be understood that when a layer, region or element is referred to as being “formed on” another layer, region or element, it may be directly or indirectly formed on the other layer, region or element. That is, for example, intervening layers, regions or elements may be present.

[0052] For the convenience of explanation, the size of the elements in the drawings may be exaggerated or reduced. For example, since the size and thickness of the elements in the drawings are arbitrarily shown for the convenience of explanation, the present disclosure is not limited thereto.

[0053] When the embodiments can be implemented differently, a specific process order can be performed differently from the described order. For example, two processes described in succession can be performed substantially simultaneously, or in an order opposite to the described order.

[0054] In the present specification, "A and / or B" means A or B, or A and B. In addition, "at least one of A and B" means A or B, or A and B.

[0055] It will be understood that when a layer, region or element is referred to as being "connected", the layer, region or element may be directly connected and / or may be indirectly connected via intervening layers, regions or elements. For example, it will be understood that when a layer, region or element is referred to as being "electrically connected" to another layer, region or element, it may mean being "directly electrically connected" to the other layer, region or element, or may be "indirectly electrically connected" to the other layer, region or element via other intervening layers, regions or elements.

[0056] In the following disclosure, it will be understood that when a wiring is referred to as "extending in the first direction or the second direction", it may extend not only in a linear shape but also in a zigzag or curved line in the first direction or the second direction.

[0057] In the embodiments described below, when referred to as "in a plan view", it means when the object is viewed from above, and when referred to as "in a cross-sectional view", it means when a cross section formed by vertically cutting the object is viewed from the side. In the embodiments described below, when a first element "overlaps" a second element, this means that the first element is disposed above or below the second element.

[0058] The x-axis, y-axis, and z-axis are not limited to the three axes of the rectangular coordinate system and can be interpreted in a broader sense. For example, the x-axis, y-axis, and z-axis can be perpendicular to each other, or can represent different directions that are not perpendicular to each other.

[0059] Figure 1 is a plan view schematically showing a display device 1 according to an embodiment.

[0060] refer to Figure 1The display device 1 may include a display panel 10 and a plurality of integrated circuits 40 for driving the display panel 10 .

[0061] The display panel 10 may include a display area DA for realizing an image, and a non-display area NDA outside the display area DA. The display area DA may be completely surrounded by the non-display area NDA.

[0062] In the display area DA of the display panel 10, pixels PX having various display elements such as organic light emitting diodes may be arranged. The pixel PX may include a plurality of pixels PX, and the plurality of pixels PX may be arranged in various forms such as stripe arrangement, Arrangement or mosaic arrangement to achieve an image.

[0063] In a plan view, the display area DA may be configured in a rectangular shape, such as Figure 1 Alternatively, the display area DA may be provided in other polygonal shapes such as a triangle, a pentagon, or a hexagon, or may be provided in a circular shape, an elliptical shape, or an amorphous shape.

[0064] The non-display area NDA of the display panel 10 is an area in which an image is not displayed and may not have pixels PX arranged therein. In the non-display area NDA, various lines configured to transmit electrical signals to be applied to elements arranged in the display area DA, a driving circuit, and first pads PAD1 connected to the lines may be arranged.

[0065] Each of the plurality of integrated circuits 40 may be mounted on the circuit board 30. The plurality of integrated circuits 40 may be mounted on the circuit board 30 by using a chip on plastic (COP) method or a chip on glass (COG) method.

[0066] Wires connecting the plurality of integrated circuits 40 with the second pads PAD2 may be disposed on the circuit board 30 , and the plurality of integrated circuits 40 may be connected to the display panel 10 through the wires and the second pads PAD2 .

[0067] Some of the plurality of integrated circuits 40 may generate electrical signals to be transmitted to the driving circuit. Other circuits in the plurality of integrated circuits 40 may generate electrical signals to be transmitted to the driving electrode lines and the detecting electrode lines.

[0068] The display device 1 may be an organic light-emitting display including a display element (e.g., an organic light-emitting diode) whose brightness varies according to an electric current. Alternatively, the display device 1 may be an inorganic light-emitting display (or an inorganic electroluminescent (EL) display) or a quantum dot light-emitting display. In other words, the emission layer of the display element provided in the display device 1 may include an organic material, an inorganic material, a quantum dot, an organic material and a quantum dot, an inorganic material and a quantum dot, or an organic material, an inorganic material and a quantum dot. In the following, the case where the display device 1 is an organic light-emitting display is mainly described.

[0069] Figure 2 is a cross-sectional view schematically showing a display device 1 according to one or more embodiments.

[0070] refer to Figure 2 , the display device 1 may include a display panel 10 and a cover window CW covering the display panel 10 .

[0071] The display panel 10 may include a substrate 100 , a display element layer 200 , an encapsulation layer 300 , and a touch sensor layer 400 .

[0072] The substrate 100 may include an insulating material such as glass, quartz or a polymer resin. The substrate 100 may be a rigid substrate, or a flexible substrate that is bendable, foldable, rollable, etc. For example, the substrate 100 may include a polymer resin such as polyethersulfone, polyacrylate, polyetherimide, polyethylene naphthalate, polyethylene terephthalate, polyphenylene sulfide, polyarylate, polyimide, polycarbonate or cellulose acetate propionate. The substrate 100 may have a multilayer structure including a layer including the above-mentioned polymer resin and an inorganic layer (not shown). For example, the substrate 100 may include two layers including the above-mentioned polymer resin and an inorganic barrier layer located therebetween.

[0073] The display element layer 200 may be disposed on the substrate 100. The display element layer 200 includes pixels and may be a layer for displaying an image. The display element layer 200 may include a display element and a pixel circuit electrically connected to the display element. In addition, the display element layer 200 may include a scan line, a data line, a power line, etc. connected to the pixel circuit, a scan drive unit for applying a scan signal to the scan line, a fan-out wiring for connecting the data line to the display drive unit, etc.

[0074] The encapsulation layer 300 for sealing the display element may be disposed on the display element layer 200. The encapsulation layer 300 may include at least one organic encapsulation layer and provide a flatter base surface. Therefore, even when the touch sensor layer 400 is formed by a continuous process, the defect rate may be reduced.

[0075] The touch sensor layer 400 may be disposed on the encapsulation layer 300. The touch sensor layer 400 may include a touch sensor and a signal line connected to the touch sensor, and may be a layer for detecting whether a user's touch has been input and a touched position. The touch sensor layer 400 may measure a capacitance change of a driving electrode and a sensing electrode included in the touch sensor, and detect whether a user's touch has been input and a touched position by using a capacitance method.

[0076] The touch sensor layer 400 may be formed together with the encapsulation layer 300 by a continuous process, such as Figure 2 For example, the touch sensor layer 400 may be directly formed on the base surface provided by the encapsulation layer 300 .

[0077] In another embodiment, the touch sensor layer 400 may be provided as a functional module separated from the display panel 10 and arranged between the display panel 10 and the cover window CW. In this case, the touch sensor layer 400 may be coupled to the display panel 10 by using an optically clear adhesive OCA or an optically clear resin.

[0078] The cover window CW may be provided throughout the display panel 10. The cover window CW may serve to protect the upper surface of the display panel 10. The cover window CW may be coupled to the display panel 10 by using an optically clear adhesive OCA or an optically clear resin.

[0079] Figure 3 is a block diagram schematically showing a display device 1 according to an embodiment.

[0080] refer to Figure 3 The display device 1 may include a display unit 11 , a gate driver 12 , a data driver 13 , a timing controller 14 , and a voltage generator 15 .

[0081] The display unit 11 may include pixels PX, such as a pixel PXij located in the i-th row and the j-th column. Figure 3 Only one pixel PXij is shown in FIG, but m×n pixels PXij may be arranged in a matrix form, for example. Here, i is a natural number between 1 and m, and j is a natural number between 1 and n.

[0082] exist Figure 3 In the present invention, for the purpose of illustration only, the description focuses on a pixel PX including two transistors and one capacitor. However, one or more embodiments are not only applicable to the above-mentioned specific pixel circuit, but also may be equally applicable to other pixel circuits, for example, a pixel PX using a pixel circuit including three transistors and one capacitor, a pixel PX using a pixel circuit including seven transistors and one capacitor, etc.

[0083] The pixels PX may be connected to the scan lines SL_1 to SL_m, the data lines DL_1 to DL_n, and the power line PL. For example, the pixel PXij located in the i-th row and the j-th column may be connected to the scan line SL_i, the data line DL_j, and the power line PL.

[0084] The data lines DL_1 to DL_n may extend in a first direction (or column direction) DR1 and may be connected to pixels PX located in the same column. The scan lines SL_1 to SL_m may extend in a second direction (or row direction) DR2 and may be connected to pixels PX located in the same row.

[0085] The power lines PL may include a plurality of vertical power lines extending in a first direction DR1, and the plurality of vertical power lines may be connected to the power lines PL located in the same column. The power lines PL may include a plurality of horizontal power lines extending in a second direction DR2, and the plurality of horizontal power lines may be connected to the power lines PL located in the same row. The plurality of horizontal power lines and the plurality of vertical power lines may be connected to each other.

[0086] Each of the scan lines SL_1 to SL_m may transmit a corresponding scan signal among the scan signals Sn_1 to Sn_m output from the gate driver 12 to the pixels PX in the same row. Each of the data lines DL_1 to DL_n may transmit a corresponding scan signal among the data signals Dm_1 to Dm_n output from the data driver 13 to the pixels PX in the same column. The pixel PXij located in the i-th row and the j-th column may receive the scan signal Sn_i and the data signal Dm_j.

[0087] The power line PL may transfer the first driving voltage ELVDD output from the voltage generator 15 to the pixel PX.

[0088] The pixel PXij may include a display element and a drive transistor configured to control the amount of current flowing to the display element based on a data signal Dm_j. The data signal Dm_j may be output from a data driver 13 and received in the pixel PXij through a data line DL_j. For example, the display element may be an organic light emitting diode. The pixel PXij emits light having a brightness corresponding to the amount of current received from the drive transistor to represent a grayscale corresponding to the data signal Dm_j. The pixel PX may correspond to a portion of a unit pixel capable of displaying full color, for example, a sub-pixel. The pixel PXij may include at least one switching transistor and at least one capacitor.

[0089] The voltage generator 15 may generate a voltage required to drive the pixel PXij. For example, the voltage generator 15 may generate a first driving voltage ELVDD and a second driving voltage ELVSS. The level of the first driving voltage ELVDD may be higher than that of the second driving voltage ELVSS.

[0090] The voltage generator 15 may generate an initialization voltage and provide the initialization voltage to the pixel PX. The initialization voltage may be applied to a gate of a driving transistor and / or an anode of a display element.

[0091] In addition, the voltage generator 15 may generate an on voltage and an off voltage for controlling a switching transistor of the pixel PXij, and provide the voltage to the gate driver 12. When the on voltage is applied to the gate of the switching transistor, the switching transistor is turned on, and when the off voltage is applied to the gate of the switching transistor, the switching transistor may be turned off. The voltage generator 15 may generate a gamma reference voltage and provide the gamma reference voltage to the data driver 13.

[0092] The timing controller 14 may control the operation timing of the gate driver 12 and the data driver 13 to control the display unit 11. The pixels PX of the display unit 11 may receive a new data signal Dm (see Figure 4 ), and emits light having a brightness corresponding to the data signal Dm to display an image corresponding to the image source data RGB of one frame.

[0093] The timing controller 14 may receive image source data RGB and a control signal CONT from the outside. The timing controller 14 may convert the image source data RGB into image data DATA based on the characteristics of the display unit 11 and the pixel PX. The timing controller 14 may provide the image data DATA to the data driver 13.

[0094] The control signal CONT may include a vertical synchronization signal, a horizontal synchronization signal, a data enable signal, a clock signal, etc. The timing controller 14 may control the operation timing of the gate driver 12 and the data driver 13 by using the control signal CONT. The timing controller 14 may determine the frame period by counting the data enable signal of the horizontal scanning period. In this case, the vertical synchronization signal and the horizontal synchronization signal provided from the outside may be omitted. The image source data RGB may include brightness information of the pixel PX. The brightness may have a set number of gray levels, such as 1024 (=2 10 )、256(=2 8 ) or 64(=2 6 ).

[0095] The timing controller 14 may generate control signals including a gate timing control signal GDC for controlling the operation timing of the gate driver 12 and a data timing control signal DDC for controlling the operation timing of the data driver 13 .

[0096] The gate timing control signal GDC may include a gate start pulse, a gate shift clock, a gate output enable signal, etc. The gate start pulse may be provided to the gate driver 12, which generates a first scan signal at the start point of the scan cycle. The gate shift clock is a clock signal commonly input to the gate driver 12, and may be a clock signal for shifting the gate start pulse. The gate output enable signal may control the output of the gate driver 12.

[0097] The data timing control signal DDC may include a source start pulse, a source sampling clock, a source output enable signal, etc. The source start pulse may control the starting time point of data sampling of the data driver 13, and may be provided to the data driver 13 at the starting time point of the scanning period. The source sampling clock may be a clock signal for controlling the sampling operation of data within the data driver 13 based on a rising edge or a falling edge. The source output enable signal may control the output of the data driver 13. On the other hand, the source start pulse provided to the data driver 13 may be omitted according to the data transmission method.

[0098] In response to the gate timing control signal GDC provided from the timing controller 14, the gate driver 12 can sequentially provide the scan signals Sn_1 to Sn_m by using the on voltage or the off voltage provided from the voltage generator 15. The gate driver 12 may include a plurality of transistors and may be formed together with the pixel PX by a thin film process. For example, the gate driver 12 may be installed in the non-display area NDA in the form of an amorphous silicon TFT gate driver circuit (ASG) or an oxide semiconductor TFT gate driver circuit (OSG).

[0099] In response to the data timing control signal DDC provided from the timing controller 14, the data driver 13 may sample and latch the image data DATA provided from the timing controller 14, and convert the image data DATA into data in a parallel data system. When performing the conversion into the data in the parallel data system, the data driver 13 may convert the image data DATA into a gamma reference voltage, and convert the gamma reference voltage into an analog data signal. The data driver 13 may provide data signals Dm_1 to Dm_n to the pixels PX through the data lines DL_1 to DL_n. The pixels PX may receive the data signals Dm_1 to Dm_n in response to the scan signals Sn_1 to Sn_m.

[0100] Figure 4is an equivalent circuit diagram of a pixel PX included in a display device according to an embodiment.

[0101] refer to Figure 4 , the pixel PX may include a pixel circuit PC connected to the scan line SL and the data line DL, and a display element connected to the pixel circuit PC. The display element may be an organic light emitting diode OLED, which includes a pixel electrode (anode) and an opposite electrode (cathode). The opposite electrode of the organic light emitting diode OLED may be a common electrode to which the second driving voltage ELVSS is applied.

[0102] The pixel circuit PC may include a first transistor T1, a second transistor T2, and a storage capacitor Cst.

[0103] The first transistor T1 may be a driving transistor in which the magnitude of the driving current Id is determined according to the gate-source voltage, and the second transistor T2 may be a switching transistor that is turned on or off according to the gate-source voltage (substantially the gate voltage). The first transistor T1 and the second transistor T2 may be formed as thin film transistors.

[0104] The first transistor T1 may be referred to as a driving transistor, and the second transistor T2 may be referred to as a scanning transistor.

[0105] The storage capacitor Cst may be connected to the power line PL and the gate of the first transistor T1. The storage capacitor Cst may have a second electrode connected to the power line PL and a first electrode connected to the gate of the first transistor T1. The storage capacitor Cst may store a voltage corresponding to a voltage difference between a voltage received from the second transistor T2 and a first driving voltage ELVDD supplied to the power line PL.

[0106] The first transistor T1 may control the magnitude of a driving current Id flowing from the power line PL to the organic light emitting diode OLED according to a gate-source voltage. The organic light emitting diode OLED may emit light having a certain brightness according to the driving current Id. The first transistor T1 may include a gate connected to a first electrode of the storage capacitor Cst, a first terminal connected to the power line PL, and a second terminal connected to the organic light emitting diode OLED.

[0107] The second transistor T2 may transmit the data signal Dm to the gate of the first transistor T1 in response to the scan signal Sn. The second transistor T2 may include a gate connected to the scan line SL, a drain connected to the data line DL, and a source connected to the gate of the first transistor T1.

[0108] exist Figure 4In the embodiment, the pixel circuit PC includes two transistors and one storage capacitor. However, one or more embodiments are not limited thereto. For example, the pixel circuit PC may include three or more transistors and / or two or more storage capacitors. In an embodiment, the pixel circuit PC may include three transistors and one storage capacitor. In another embodiment, the pixel circuit PC may include seven transistors and one storage capacitor.

[0109] Figure 5 It is schematically shown Figure 1 0 is a cross-sectional view of the display device 1 shown in FIG. 1 , taken along line II′.

[0110] refer to Figure 5 The display element layer 200, the encapsulation layer 300, and the touch sensor layer 400 may be sequentially stacked on the substrate 100 in the display area DA. The organic light emitting diode OLED and the pixel circuit PC electrically connected to the organic light emitting diode OLED may be disposed on the display element layer 200.

[0111] As reference Figure 2 As described above, the substrate 100 may include an insulating material such as glass, quartz or polymer resin. The substrate 100 may be a rigid substrate, or a flexible substrate that is bendable, foldable, rollable, etc.

[0112] The buffer layer 201 may be disposed throughout the substrate 100, and may reduce or prevent penetration of impurities, moisture, or ambient air from a lower portion of the substrate 100, and provide a flat surface to the semiconductor layer Act. The buffer layer 201 may include an inorganic material such as an oxide or a nitride, an organic material, or an organic-inorganic composite material, and may include a single-layer structure or a multi-layer structure of an inorganic material and an organic material.

[0113] The barrier layer 101 may also be included between the substrate 100 and the buffer layer 201 to block the penetration of ambient air. The buffer layer 201 and the barrier layer 101 may include silicon oxide (SiO 2 ) and / or silicon nitride (SiN x ).

[0114] A pixel circuit PC including a thin film transistor TFT and a storage capacitor Cst may be disposed on the buffer layer 201. The thin film transistor TFT may correspond to the reference Figure 4 A first transistor T1 is described.

[0115] The thin film transistor TFT may include a semiconductor layer Act, a gate electrode GE, a drain electrode DE, and a source electrode SE.

[0116] The semiconductor layer Act may be disposed on the buffer layer 201 and may include polycrystalline silicon. In another embodiment, the semiconductor layer Act may include amorphous silicon. In another embodiment, the semiconductor layer Act may include an oxide of at least one material selected from the group consisting of indium (In), gallium (Ga), tin (Sn), zirconium (Zr), vanadium (V), hafnium (Hf), cadmium (Cd), germanium (Ge), chromium (Cr), titanium (Ti) and zinc (Zn). The semiconductor layer Act may include a channel region, a source region and a drain region, wherein the source region and the drain region are doped with impurities. The source region and the drain region may be arranged at opposite sides of the channel region, respectively.

[0117] The first gate insulating layer 203 may be provided to cover the semiconductor layer Act. The first gate insulating layer 203 may include an inorganic insulating material such as SiO 2 、SiN x 、Silicon Oxynitride (SiON), Aluminum Oxide (Al 2 O 3 ), titanium oxide (TiO 2 ), Tantalum Oxide (Ta 2 O 5 ), hafnium oxide (HfO 2 ) or zinc oxide (ZnO x , which may be ZnO and / or ZnO 2 ). The first gate insulating layer 203 may be a single layer or multiple layers including the above-mentioned inorganic insulating material.

[0118] The gate electrode GE may be disposed on the first gate insulating layer 203 to overlap the semiconductor layer Act. The gate electrode GE may include molybdenum (Mo), aluminum (Al), copper (Cu), Ti, and may include a single layer or multiple layers. For example, the gate electrode GE may be a single Mo layer.

[0119] The second gate insulating layer 204 may be provided to cover the gate electrode GE. The second gate insulating layer 204 may include an inorganic insulating material such as SiO 2 、SiN x 、SiON、Al 2 O 3 、TiO 2 、 2 O 5 , HfO 2 or ZnO x (It can be ZnO and / or ZnO 2 ). The second gate insulating layer 204 may be a single layer or multiple layers including the above-mentioned inorganic insulating material.

[0120] The second electrode CE2 of the storage capacitor Cst may be disposed on the second gate insulating layer 204. The second electrode CE2 may overlap the gate electrode GE. The gate electrode GE and the second electrode CE2 may form a storage capacitor Cst by overlapping each other with the second gate insulating layer 204 therebetween. In other words, the gate electrode GE may serve as the first electrode CE1 of the storage capacitor Cst.

[0121] The second electrode CE2 may include Al, platinum (Pt), palladium (Pd), silver (Ag), magnesium (Mg), gold (Au), nickel (Ni), neodymium (Nd), iridium (Ir), Cr, calcium (Ca), Mo, Ti, tungsten (W) and / or Cu, and may be a single layer or a multilayer including the above materials.

[0122] The interlayer insulating layer 205 may be formed to cover the second electrode CE2. The interlayer insulating layer 205 may include SiO 2 、SiN x 、SiON、Al 2 O 3 、TiO 2 、 2 O 5 , HfO 2 、ZnO x (It can be ZnO and / or ZnO 2 ) etc. The interlayer insulating layer 205 may be a single layer or multiple layers including the above-mentioned inorganic insulating material.

[0123] The buffer layer 201 , the first gate insulating layer 203 , the second gate insulating layer 204 , and the interlayer insulating layer 205 may be collectively referred to as an inorganic insulating layer.

[0124] The source electrode SE and the drain electrode DE may be disposed on the interlayer insulating layer 205. The source electrode SE and the drain electrode DE may include a conductive material, including Mo, Al, Cu, Ti, etc., and may be formed as a single layer or a multilayer including the above materials. For example, the source electrode SE and the drain electrode DE may have a multilayer structure of Ti / Al / Ti. In some embodiments, the source electrode SE or the drain electrode DE may be omitted. For example, adjacent thin film transistors TFT may share a source region or a drain region of the semiconductor layer Act, and the source region or the drain region may be used as the source electrode SE or the drain electrode DE, respectively.

[0125] The planarization insulating layer 207 may be disposed to cover the source electrode SE and the drain electrode DE. The planarization insulating layer 207 may provide a flat base surface for the pixel electrode 210 disposed thereon.

[0126] The planarization insulating layer 207 may include an organic material or an inorganic material, and may have a single-layer structure or a multi-layer structure. The planarization insulating layer 207 may include a general polymer such as benzocyclobutene (BCB), polyimide, hexamethyldisiloxane (HMDSO), polymethylmethacrylate (PMMA) or polystyrene (PS), a polymer derivative having a phenol-based group, an acrylic acid-based polymer, an imide-based polymer, an aryl ether-based polymer, an amide-based polymer, a fluorine-based polymer, a p-xylene-based polymer, a vinyl alcohol-based polymer, etc. The planarization insulating layer 207 may include an inorganic insulating material such as SiO 2 、SiN x 、SiON、Al 2 O 3 、TiO 2 、 2 O 5 , HfO 2 or ZnO x (It can be ZnO and / or ZnO 2 ). When the planarization insulating layer 207 is formed, a layer may be formed, and then, chemical and mechanical polishing may be performed on an upper surface of the layer to provide a planar surface.

[0127] The pixel electrode 210 may be disposed on the planarization insulating layer 207. The planarization insulating layer 207 may have a through hole exposing one of the source electrode SE and the drain electrode DE of the thin film transistor TFT, and the pixel electrode 210 may be electrically connected to the thin film transistor TFT by contacting the source electrode SE or the drain electrode DE through the through hole.

[0128] The pixel electrode 210 may include a conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium oxide (In 2 O 3 ), indium gallium oxide (IGO) or aluminum zinc oxide (AZO). The pixel electrode 210 may include a reflective film containing Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr or any compound thereof. For example, the pixel electrode 210 may have a structure including a film above / below the above-mentioned reflective film, the film including ITO, IZO, ZnO or In 2 O 3 In this case, the pixel electrode 210 may have a stack structure of ITO / Ag / ITO.

[0129] The pixel defining layer 209 may cover the edge of the pixel electrode 210 on the planarization insulating layer 207, and may have a pixel opening OP1 exposing a central portion of the pixel electrode 210. The emission area EA of the organic light emitting diode OLED (ie, the size and shape of the pixel) may be defined by the pixel opening OP1.

[0130] The pixel defining layer 209 can prevent arcing, etc., from occurring at the edge of the pixel electrode 210 by increasing the distance between the edge of the pixel electrode 210 and the opposite electrode 230. The pixel defining layer 209 may be an organic insulating material such as polyimide, polyamide, acrylic resin, BCB, HMDSO, and phenolic resin, and may be formed by a spin coating method, etc.

[0131] The pixel defining layer 209 may be formed in black. The pixel defining layer 209 includes a light blocking material and may be provided in black. The light blocking material may include carbon black, carbon nanotubes, a resin or a slurry including a black dye, metal particles such as Ni, Al, Mo and any alloy thereof, metal oxide particles (e.g., chromium oxide), metal nitride particles (e.g., chromium nitride), etc. When the pixel defining layer 209 includes a light blocking material, external reflection caused by a metal structure disposed below the pixel defining layer 209 may be reduced.

[0132] The intermediate layer 220 may be disposed between the pixel electrode 210 and the opposite electrode 230. The intermediate layer 220 may include a first functional layer 221, an emission layer 222, and a second functional layer 223.

[0133] An emission layer 222 formed to correspond to the pixel electrode 210 may be disposed in the pixel opening OP1 of the pixel defining layer 209. The emission layer 222 may include a polymer material or a low molecular weight material, and may emit red, green, blue, or white light.

[0134] The first and second functional layers 221 and 223 may be respectively disposed under and / or over the emission layer 222. In an embodiment, unlike the emission layer 222 arranged and patterned for each pixel, the first and second functional layers 221 and 223 may be integrally provided across the entire surface of the display area DA.

[0135] The first functional layer 221 may be a single layer or a multilayer. For example, when the first functional layer 221 includes a polymer material, the first functional layer 221 is a hole transport layer having a single layer structure and may include poly-(3,4)-ethylene-dihydroxythiophene (PEDOT) or polyaniline (PANI). When the first functional layer 221 includes a low molecular weight material, the first functional layer 221 may include a hole injection layer and a hole transport layer.

[0136] The second functional layer 223 may be selectively arranged. For example, when the first functional layer 221 and the emission layer 222 include a polymer material, it may be necessary to form the second functional layer 223. The second functional layer 223 may be a single layer or a multilayer. The second functional layer 223 may include an electron transport layer and / or an electron injection layer. In some embodiments, at least one of the hole injection layer, the hole transport layer, the electron transport layer, and the electron injection layer may be omitted.

[0137] The counter electrode 230 may include a conductive material having a relatively low work function. For example, the counter electrode 230 may include a (semi) transparent layer including Ag, Mg, Al, Ni, Cr, Li, Ca or any alloy thereof. Alternatively, the counter electrode 230 may also include a conductive material including ITO, IZO, ZnO or In over the (semi) transparent layer including the above materials. 2 O 3 In an implementation, the opposite electrode 230 may include Ag and Mg.

[0138] The stack structure of the pixel electrode 210 , the intermediate layer 220 , and the opposite electrode 230 stacked sequentially may form an organic light emitting diode OLED.

[0139] In an embodiment, a coating layer (not shown) may be disposed on the organic light emitting diode OLED. Through the principle of constructive interference, the coating layer may improve the emission efficiency of the organic light emitting diode OLED. The coating layer may include an organic coating layer including an organic material, an inorganic coating layer including an inorganic material, or a composite coating layer including an organic material and an inorganic material.

[0140] The encapsulation layer 300 may be disposed on the organic light emitting diode OLED. In an embodiment, the encapsulation layer 300 may include at least one inorganic encapsulation layer and at least one organic encapsulation layer. For example, the encapsulation layer 300 may include a first inorganic encapsulation layer 310 and a second inorganic encapsulation layer 330 and an organic encapsulation layer 320 located therebetween.

[0141] Each of the first inorganic encapsulating layer 310 and the second inorganic encapsulating layer 330 may include one or more inorganic insulating materials. The inorganic insulating material may include Al 2 O 3 、TiO 2 、 2 O 5 , HfO 2 、ZnO x (It can be ZnO and / or ZnO 2 )、SiO x 、SiN xand / or SiON. The first inorganic encapsulating layer 310 and the second inorganic encapsulating layer 330 may be formed by chemical vapor deposition.

[0142] The organic encapsulating layer 320 may include polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyvinyl sulfonate, polyoxymethylene, polyarylate, HMDSO, an acrylic-based resin, or any combination thereof.

[0143] The encapsulation layer 300 covers the entire display area DA, and may be arranged to extend to the non-display area NDA and cover at least a portion of the non-display area NDA.

[0144] As described above, the encapsulation layer 300 may include the organic encapsulation layer 320 and provide a flatter base surface. Therefore, even when the elements of the touch sensor layer 400 are formed by a continuous process, the defect rate may be reduced.

[0145] The touch sensor layer 400 may have a multi-layer structure. The touch sensor layer 400 may include a detection electrode, a detection signal line connected to the detection electrode, a drive electrode, a drive signal line connected to the drive electrode, and at least one insulating layer. For example, the touch sensor included in the touch sensor layer 400 may detect an external input according to a capacitive method.

[0146] The touch sensor layer 400 may include a first touch insulating layer 410 , a first touch conductive layer MTL1 , a second touch insulating layer 420 , a second touch conductive layer MTL2 , and a third touch insulating layer 430 .

[0147] The first touch insulating layer 410 may be directly disposed on the encapsulation layer 300. The first touch insulating layer 410 includes an inorganic material or an organic material, and may be disposed as a single layer or a multi-layer.

[0148] The first touch insulation layer 410 may prevent damage to the encapsulation layer 300 and block interference signals that may occur when the touch sensor layer 400 is driven.

[0149] For example, each of the first touch conductive layer MTL1 and the second touch conductive layer MTL2 may have a single-layer structure or a stacked multi-layer structure. The single-layer conductive layer may include a metal layer or a transparent conductive layer. The metal layer may include Mo, Ag, Ti, Cu, Al, and any alloy thereof. The transparent conductive layer may include a transparent conductive oxide such as ITO, IZO, ZnO, or ITZO. In addition, the transparent conductive layer may include a conductive polymer such as PEDOT, a metal nanowire, graphene, etc.

[0150] The multilayer conductive layer may include a plurality of metal layers. The plurality of metal layers may have a three-layer structure of, for example, Ti / Al / Ti. The multilayer conductive layer may include at least one metal layer and at least one transparent conductive layer.

[0151] Each of the first touch conductive layer MTL1 and the second touch conductive layer MTL2 may include a plurality of patterns. It is understood that the first touch conductive layer MTL1 includes a first conductive pattern, and the second touch conductive layer MTL2 includes a second conductive pattern. The first conductive pattern and the second conductive pattern may form a touch sensor.

[0152] The first touch conductive layer MTL1 and the second touch conductive layer MTL2 may be electrically connected to each other through a contact hole. In an embodiment, the first touch conductive layer MTL1 and the second touch conductive layer MTL2 may have a mesh structure so that light emitted from the organic light emitting diode OLED can pass through. In this case, the first touch conductive layer MTL1 and the second touch conductive layer MTL2 may be arranged not to overlap with the emission area EA.

[0153] The second touch insulating layer 420 may include an organic material. The organic material may include at least one material selected from the group consisting of acrylic-based resins, methacrylic-based resins, polyisoprene, ethylene-based resins, epoxy-based resins, urethane-based resins, cellulose-based resins, and perylene-based resins. The second touch insulating layer 420 may also include an inorganic material. The inorganic material may include a material selected from the group consisting of SiN x 、Aluminum nitride (AlN), zirconium nitride (ZrN), titanium nitride (TiN), hafnium nitride (HfN), tantalum nitride (TaN), SiO x 、Al 2 O 3 、TiO 2 , Tin Oxide (SnO 2 ), cerium oxide (CeO 2 ) and at least one material of the group consisting of SiON.

[0154] The third touch insulating layer 430 may be disposed on the second touch conductive layer MTL2. The third touch insulating layer 430 may have a single layer or multi-layer structure. The third touch insulating layer 430 may include an organic material, an inorganic material, or a composite material.

[0155] exist Figure 5 In the embodiment, the touch sensor layer 400 is directly formed on the encapsulation layer 300, and the display panel 10 (see Figure 2) includes a touch sensor layer 400. However, one or more embodiments are not limited thereto. In another embodiment, the touch sensor layer 400 may be provided as a functional module separated from the display panel 10 and coupled to the display panel 10 via an optically transparent adhesive OCA.

[0156] Figure 6 Schematically illustrates a touch detection device TSD included in a display device according to an embodiment. Figure 6 , the touch detection device TSD may include a touch sensor TS arranged in the touch detection area TSA, and a touch integrated circuit TIC configured to control the touch sensor TS.

[0157] The touch sensor TS may include a driving electrode line TEL and a detecting electrode line REL. The driving electrode line TEL may include a plurality of driving electrodes (also referred to as driving electrode units) TE and a plurality of first connection electrodes CTE1 (see Fig. 7A ), and the detection electrode line REL may include a plurality of detection electrodes (also referred to as detection electrode units) RE and a plurality of second connection electrodes CTE2 (see Figure 7B ). The driving electrode lines TEL may extend in a first direction (x direction), and the detecting electrode lines REL may extend in a second direction (y direction). The driving electrode lines TEL and the detecting electrode lines REL may be arranged to cross each other in a plan view.

[0158] The driving electrode line TEL may include a plurality of driving electrode lines TEL, and the detecting electrode line REL may include a plurality of detecting electrode lines REL. The plurality of driving electrode lines TEL may be arranged separately from each other in the second direction (y direction), and the plurality of detecting electrode lines REL may be arranged separately from each other in the first direction (x direction).

[0159] The touch integrated circuit TIC can correspond to Figure 1 At least one of the plurality of integrated circuits 40 shown in FIG. 4. In an embodiment, the touch integrated circuit TIC may be mounted on the circuit board 30 (see FIG. Figure 1 )superior.

[0160] The touch integrated circuit TIC may include a signal driving unit 51, a signal detection unit 53, and a memory 55. The signal driving unit 51 may be electrically connected to the driving electrode line TEL through the driving signal line TL, and may apply the driving signal Tx to the driving electrode line TEL. The signal detection unit 53 may be electrically connected to the detection electrode line REL through the detection signal line RL, and may receive a detection signal Rx from the detection electrode line REL, and convert the detection signal Rx into a digital signal.

[0161] The signal detection unit 53 may include an analog front end (AFE) for receiving an analog signal, and an analog-to-digital converter (ADC) for converting the analog signal into a digital signal. The memory 55 may store software, algorithms, etc. for operating the touch integrated circuit TIC. The memory 55 may include a random access memory (RAM) and / or a flash memory.

[0162] The control unit 60 may control the operation of the touch integrated circuit TIC and determine whether a touch input is received and the position of the touch based on the detection signal received from the touch integrated circuit TIC. The control unit 60 may include a microcontroller unit (MCU) and / or a central processing unit (CPU). In an embodiment, the control unit 60 may be included in the touch integrated circuit TIC. For example, Figure 6 As shown in , the touch integrated circuit TIC may be provided as a single chip including the control unit 60 .

[0163] The touch integrated circuit TIC can sense the change of the mutual capacitance between the driving electrode line TEL and the detection electrode line REL, the change of the self-capacitance of the driving electrode line TEL, and / or the change of the self-capacitance of the detection electrode line REL. The touch integrated circuit TIC can generate a detection signal based on the change of the mutual capacitance and / or the change of the self-capacitance, and transmit the generated detection signal to the control unit 60. The control unit 60 can determine whether a touch input is received and the position of the touch based on the detection signal, and control the operation mode of the touch integrated circuit TIC.

[0164] Fig. 7A , Figure 7B and Figure 7C is a plan view schematically showing a part of the touch detection area TSA. Fig. 7A The first touch conductive layer MTL1 (see FIG. Figure 5 ),as well as Figure 7B The second touch conductive layer MTL2 (see FIG. Figure 5 ). Figure 7C It is shown Fig. 7A An enlarged plan view of region III in FIG.

[0165] refer to Fig. 7A and Figure 7B , the driving electrodes TE and the detecting electrodes RE included in the touch sensor may be arranged in the touch detection area TSA.

[0166] The driving electrodes TE may be arranged in a first direction (x direction) and a second direction (y direction). The driving electrodes TE adjacent to each other in the first direction (x direction) may be connected to each other through a first connection electrode CTE1 disposed on the first touch conductive layer MTL1. The driving electrodes TE and the first connection electrodes CTE1 may be integrally disposed as a single body. The driving electrodes TE and the first connection electrodes CTE1 connected to each other in the first direction (x direction) may form a driving electrode line TEL (see Figure 6 ).

[0167] The detection electrodes RE may be arranged in the first direction (x direction) and the second direction (y direction). The detection electrodes RE adjacent to each other in the second direction (y direction) may be connected to each other through the second connection electrode CTE2 provided on the second touch conductive layer MTL2. The second connection electrode CTE2 may be connected to the detection electrode RE through the contact hole CNT. The detection electrode RE and the second connection electrode CTE2 connected to each other in the second direction (y direction) may form a detection electrode line REL (see Figure 6 ).

[0168] refer to Fig. 7A and Figure 7B as well as Figure 6 In a plan view, the driving electrode line TEL and the detecting electrode line REL may be arranged to cross each other. For example, in a plan view, the first connection electrode CTE1 of the driving electrode line TEL and the second connection electrode CTE2 of the detecting electrode line REL may be arranged to cross each other. Because an insulating layer (e.g., a second touch insulating layer 420) is located between the first connection electrode CTE1 and the second connection electrode CTE2, the first connection electrode CTE1 and the second connection electrode CTE2 overlapping each other may form a capacitor.

[0169] The driving electrode TE and the detecting electrode RE may have a mesh (or grid, grid) pattern. The metal pattern extending in the third direction DR3 and the metal pattern extending in the fourth direction DR4 may cross each other to form a mesh pattern, and the third direction DR3 crosses the first direction (x direction) and the second direction (y direction). Therefore, the driving electrode TE and the detecting electrode RE may have a plurality of electrode openings. Similarly, the first connection electrode CTE1 and the second connection electrode CTE2 may have a mesh (or grid, grid) pattern.

[0170] refer to Figure 7C , the driving electrode TE may have a mesh pattern. The driving electrode TE may define a plurality of electrode openings EOP located within a matrix of the mesh pattern. Each of the electrode openings EOP may be arranged to overlap with one pixel PX. In other words, the emission area EA of one pixel PX (see Figure 5) may be arranged within each of the electrode openings EOP.

[0171] The detection electrode RE may have Figure 7C Even when the driving electrode TE and the detecting electrode RE include a metal layer, light emitted from the pixel PX may transmit the touch sensor layer 400 through the electrode opening EOP (see FIG. Figure 5 ).

[0172] In an embodiment, Fig. 7A and Figure 7B Unlike the example shown in FIG. 1 , the driving electrode TE, the first connection electrode CTE1 and the detection electrode RE are arranged on the second touch conductive layer MTL2 (see FIG. 1 ). Figure 5 ), and the second connection electrode CTE2 may be disposed on the first touch conductive layer MTL1 (see Figure 5 ). In an implementation, the driving electrode TE and the detecting electrode RE may have a surface pattern including a transparent conductive material.

[0173] Figure 8 is a diagram for describing a sensing principle of a display device according to an embodiment.

[0174] refer to Figure 8 , the touch sensor may include a touch capacitor Ct. The touch capacitor Ct may include a first electrode ELt and a second electrode ELr overlapping the first electrode ELt. For example, the first electrode ELt may correspond to Figure 6 A region of the driving electrode line TEL shown in FIG. 1 , and the second electrode ELr may correspond to Figure 6 The first electrode ELt may correspond to the first connection electrode CTE1 of the driving electrode line TEL (see Fig. 7A ), and the second electrode ELr may correspond to the second connection electrode CTE2 of the detection electrode line REL (see Figure 7B ).

[0175] A mutual capacitance Cm may be generated between the first electrode ELt and the second electrode ELr which overlap each other with the insulating layer therebetween in a plan view.

[0176] When a contact object F such as a finger or a stylus pen contacts the upper surface of the touch capacitor Ct, the mutual capacitance Cm may change between the first electrode ELt and the second electrode ELr. Figure 6 ) can be electrically connected to the first electrode ELt by the driving signal line TL (see Figure 6 ) is applied to the touch capacitor Ct, and can be detected by using the detection signal Rx (see Figure 6 ) to sense the mutual capacitance Cm. Since the position of the touch capacitor Ct can be specified, whether a touch input is received and the touch position (touch coordinates) can be determined by the change in the mutual capacitance Cm.

[0177] When the contact object F contacts or is adjacent to the upper surface of the touch capacitor Ct, a first self-capacitance Cap_s1 may be generated between the first electrode ELt and the contact object F. Similarly, a second self-capacitance Cap_s2 may be generated between the second electrode ELr and the contact object F. Based on a change in the first self-capacitance Cap_s1 or a change in the second self-capacitance Cap_s2, it may be determined whether the contact object F is approaching and whether a touch input is received. The touch integrated circuit TIC may sense a portion or all of the mutual capacitance Cm, the first self-capacitance Cap_s1, and the second self-capacitance Cap_s2.

[0178] Fig. 9 It is a diagram for describing a display device and a sensing principle of the display device according to an embodiment. The description focuses on the following case: the first electrode ELt shown in the following figure is a first connection electrode of a driving electrode line, and the second electrode ELr is a second connection electrode of a detection electrode line. In the following, applying a driving signal to a driving electrode line and applying a driving signal to the first electrode ELt can be understood as having substantially the same meaning.

[0179] According to an embodiment, a display device may include a touch integrated circuit TIC, which includes a signal driving unit 51 and a signal detection unit 53, a plurality of switches SW and a test resistor RT, the signal driving unit 51 applies a driving signal Tx to a driving electrode line (or a first electrode ELt), and the signal detection unit 53 receives a detection signal Rx from the detection electrode line (or a second electrode ELr), a plurality of switches SW connect the signal driving unit 51 to the driving electrode line (or the first electrode ELt), and the test resistor RT is connected to the driving electrode line (or the first electrode ELt) through at least one of the plurality of switches SW.

[0180] refer to Fig. 9 , the plurality of switches SW may be connected in parallel and may be included in the signal driving unit 51 of the touch integrated circuit TIC. The plurality of switches SW may be connected in parallel and may be included in the signal driving unit 51 of the touch integrated circuit TIC. Figure 6 ) is selectively turned on by a control signal. In an embodiment, a plurality of driving electrode lines TEL (see Figure 6 ) can be connected to multiple switches SW respectively.

[0181] In an embodiment, the plurality of switches SW may include a first switch SW1 and a second switch SW2. The second switch SW2 may be connected to a test resistor RT, and when the second switch SW2 is turned on, the test resistor RT may be connected to the first electrode ELt. When the first switch SW1 is turned on, the drive signal Tx may be transmitted to the first electrode ELt without passing through the additional test resistor RT, and when the second switch SW2 is turned on, the drive signal Tx may pass through the test resistor RT and may be converted into a specific test drive signal and transmitted to the first electrode ELt.

[0182] The size of the test resistor RT included in the display device according to the embodiment may be selected so that when at least one switch (in Fig. 9 In the embodiment, the mutual capacitance Cm generated when the second switch SW2) connects the test resistor RT to the first electrode ELt has a value corresponding to the mutual capacitance Cm generated when the user (for example, using a finger) directly touches the display device. As used herein, the value "corresponding to" the mutual capacitance Cm refers to a value within 5% of the mutual capacitance Cm generated in the case of direct touch. In other words, the size of the test resistor RT can be selected so that the mutual capacitance Cm generated when the test resistor RT is connected to the first electrode ELt has substantially the same value as the mutual capacitance Cm generated when the user directly touches the display device. In an embodiment, the test resistor RT may be in a range from 800Ω to 1200Ω. Refer to the following FIG. 10A to FIG. 12B Provide a detailed description thereof.

[0183] Generally, a test of whether a touch operation of a display device is performed (the test includes a capacitive touch detection device) can be performed by allowing a contact object such as a human finger to contact the touch sensor and by detecting data before and after the finger touch (e.g., a change in capacitance), and it can be determined whether a touch input is received at a predetermined test coordinate. In this case, because the data is affected by the size of the tester's finger, the degree of adhesion, etc., the accuracy of the test may be unreliable and may consume a considerable amount of time.

[0184] A method for testing a display device according to an embodiment includes: sensing a first mutual capacitance of a predetermined test coordinate by applying a first drive signal to a drive electrode line; sensing a second mutual capacitance of a predetermined test coordinate by applying a second drive signal to the drive electrode line; and determining whether a touch operation is performed by detecting the difference between the first mutual capacitance and the second mutual capacitance. The difference between the first mutual capacitance and the second mutual capacitance refers to a change in mutual capacitance. The first mutual capacitance and the second mutual capacitance can be sensed by using a detection signal received from a detection signal line. Because it is possible to test whether a touch operation of the display device is performed without directly touching the contact object, the accuracy of the test can be improved and the time required for the test can be shortened. In addition, in the case of a method of controlling the application of a desired drive signal by a switch operation, a built-in switch can be used without adding a switch for testing.

[0185] Fig. 10A and Fig. 10B is a diagram for describing a method of testing a display device according to an embodiment. As an example of a method of applying a first driving signal Tx1 or a second driving signal Tx2, Fig. 10A and Fig. 10B It is shown that the first driving signal Tx1 and the second driving signal Tx2 are applied to the first electrode ELt by switch control. Fig. 10A and Fig. 10B The first electrode ELt and the second electrode ELr in the embodiment may be electrodes corresponding to predetermined test coordinates to be tested. Fig. 10A and Fig. 10B In, with Fig. 9 The same reference numerals as those in the drawings denote the same components, and their redundant descriptions are omitted.

[0186] When the first switch SW1 is turned on and the second switch SW2 is turned off, Fig. 10A As shown in FIG. 1 , the driving signal Tx of the signal driving unit 51 may be applied to the first electrode ELt as the first driving signal Tx1, and the first electrode ELt and the second electrode ELr may form a first mutual capacitance Cm1. The touch integrated circuit TIC may sense the first mutual capacitance Cm1 of a predetermined test coordinate through the detection signal Rx received by the signal detection unit 53.

[0187] When the first switch SW1 is turned off and the second switch SW2 is turned on, Fig. 10B As shown in FIG. 5 , the driving signal Tx of the signal driving unit 51 can be applied to the first electrode ELt as the second driving signal Tx2, and the first electrode ELt and the second electrode ELr can form a second mutual capacitance Cm2. The touch integrated circuit TIC can sense the second mutual capacitance Cm2 of the predetermined test coordinate through the detection signal Rx received by the signal detection unit 53.

[0188] The difference between the first drive signal Tx1 and the second drive signal Tx2 can be achieved by the difference in the size of the resistor connected to the first electrode ELt by the first switch SW1 and the second switch SW2. Unlike when the first switch SW1 is turned on, when the second switch SW2 is turned on, the test resistor RT is connected to the first electrode ELt, and therefore, a difference can occur between the first mutual capacitance Cm1 and the second mutual capacitance Cm2.

[0189] Control unit 60 (see Figure 6 ) Whether the predetermined test coordinate is touched can be determined by the difference between the first mutual capacitance Cm1 and the second mutual capacitance Cm2. When the difference between the first mutual capacitance Cm1 and the second mutual capacitance Cm2 is substantially the same as the change in mutual capacitance generated when the contact object is directly touched, it can be determined that the touch detection device operates normally.

[0190] When the touch detection device operates normally, the first mutual capacitance Cm1 corresponds to the mutual capacitance when there is no touch, and the second mutual capacitance Cm2 may correspond to the mutual capacitance when the contact object is directly touched (for example, using the user's finger). To this end, the second drive signal Tx2 may be configured so that the second mutual capacitance Cm2 according to the second drive signal Tx2 has a value corresponding to the mutual capacitance of the direct touch according to the contact object. The size of the test resistor RT may be configured so that when the second switch SW2 is turned on, the second mutual capacitance Cm2 has a value corresponding to the mutual capacitance of the direct touch according to the contact object.

[0191] In summary, the test method according to the embodiment may include: configuring the first drive signal Tx1 and the second drive signal Tx2 so that the first drive signal Tx1 corresponds to no touch and the second drive signal Tx2 corresponds to direct touch; and sequentially applying the first drive signal Tx1 and the second drive signal Tx2 to the first electrode ELt and detecting the difference in mutual capacitance. Whether the touch operation is normally detected can be determined based on whether the detected mutual capacitance difference is substantially the same as the change in mutual capacitance obtained by allowing the contact object to directly contact.

[0192] exist Fig. 9 , Fig. 10A and Fig. 10B In the embodiment, there is a switch connected to the test resistor. However, the embodiments of the present disclosure are not limited thereto. For example, there may be two switches connected to the test resistors, and one of the test resistors connected to each of the switches may be selected, or a plurality of test resistors connected to each of the switches may be used in combination.

[0193] Fig.11 is a diagram for describing a display device and a method of testing the display device according to an embodiment, and Fig. 12A and Fig. 12Bis a diagram for describing a test resistor of a display device and a method of testing the display device according to an embodiment. Fig.11 In, with Fig. 9 The same reference numerals as those in the drawings denote the same components, and their redundant descriptions are omitted.

[0194] refer to Fig.11 In an embodiment, the touch integrated circuit TIC may include three switches connected to the test resistor. When at least one of the first switch SW1, the second switch SW2, the third switch SW3, and the fourth switch SW4 is turned on, the drive signal Tx of the signal driving unit 51 may be applied to the first electrode ELt as the first drive signal Tx1 or the second drive signal Tx2. For example, when only the first switch SW1 is turned on, the first drive signal Tx1 may be applied to the first electrode ELt, and when only one of the second switch SW2, the third switch SW3, and the fourth switch SW4 is turned on, the second drive signal Tx2 may be applied to the first electrode ELt. In this case, the resistor connected to the turned-on switch may be used as the test resistor. Alternatively, when two or more switches of the second switch SW2, the third switch SW3, and the fourth switch SW4 are turned on, the second drive signal Tx2 may be applied to the first electrode ELt, and in this case, the equivalent resistance of the connected resistor may be used as the test resistor.

[0195] refer to Fig.11 , the second switch SW2 may be connected to the first test resistor RTa, the third switch SW3 may be connected to the second test resistor RTb, and the fourth switch SW4 may be connected to the third test resistor RTc. Fig. 12A An example is shown in which the size of the first test resistor RTa is 100Ω, the size of the second test resistor RTb is 500Ω, and the size of the third test resistor RTc is 1000Ω. Fig. 12B A table showing the magnitude of mutual capacitance of a predetermined test coordinate (REL2, TEL2) and adjacent coordinates is shown. The test coordinate (REL2, TEL2) may refer to a region where the test detection electrode line REL2 and the test drive electrode line TEL2 overlap each other.

[0196] The signal driving unit connected to the plurality of driving electrode lines TEL0, TEL1, TEL2, TEL3 and TEL4 may include Fig. 12ASwitches and test resistors in an embodiment. Table 1 shows a state of no touch, and Table 5 shows a state of direct hand touch at the test coordinates (REL2, TEL2). Table 1 and Table 5 show the situation where multiple drive electrode lines TEL0, TEL1, TEL2, TEL3 and TEL4 are not connected to the test resistor. Table 2, Table 3 and Table 4 respectively show the mutual capacitance of each coordinate in a state where the test resistor is connected to the test drive electrode line TEL2 and the test resistor is not connected to other drive electrode lines TEL0, TEL1, TEL3 and TEL4. Table 2 shows the situation where the test drive electrode line TEL2 is connected to a test resistor of 100Ω. Table 3 shows the situation where the test drive electrode line TEL2 is connected to a test resistor of 500Ω. Table 4 shows the situation where the test drive electrode line TEL2 is connected to a test resistor of 1000Ω.

[0197] Mainly referring to the test coordinates (REL2, TEL2) in Table 1 and Table 5, it can be seen that the mutual capacitance in these test coordinates (REL2, TEL2) changes from 1815 during no touch to 1546 in the case of hand touch. According to the above contents in Tables 2 to 4, observing the values ​​of the test coordinates (REL2, TEL2) in Tables 2 to 4, Figure 4 The case in this example is 1515, which is most similar to Figure 5 This means that when a 1000Ω resistor among the resistors of 100Ω, 500Ω, and 1000Ω is connected to the test drive electrode line TEL2, it is easier to test by comparing the mutual capacitance during hand touch with the mutual capacitance through switch operation.

[0198] Fig.13 is a diagram for describing a sensing principle of a display device according to an embodiment, and Fig.14A and Fig. 14B is a diagram for describing a display device and a method of testing the display device according to an embodiment. Fig.13 In, with Fig. 9 The same reference numerals as those in the drawings denote the same components, and their redundant descriptions are omitted.

[0199] refer to Fig.13 , the signal driving unit 51 may include a charge pump CP. The charge pump CP may increase the input voltage V applied to the signal driving unit 51 and output the voltage. In an embodiment, the signal driving unit 51 may receive a voltage of about 3V, and the charge pump CP may increase the voltage to a voltage in the range of about 3V to 6V.

[0200] According to an embodiment, a method for testing a display device includes: sensing a first mutual capacitance Cm1 of a test coordinate by applying a first drive signal Tx1 to a first electrode ELt; sensing a second mutual capacitance Cm2 of a test coordinate by applying a second drive signal Tx2 to the first electrode ELt; and determining whether a touch operation is performed by detecting a difference between the first mutual capacitance Cm1 and the second mutual capacitance Cm2.

[0201] In an embodiment, the first drive signal Tx1 and the second drive signal Tx2 may be adjusted according to the boosting degree of the charge pump CP. The charge pump CP may boost the input voltage V applied to the signal driving unit 51 to a first voltage and apply the first drive signal Tx1 to the first electrode ELt. The charge pump CP may boost the input voltage V applied to the signal driving unit 51 to a second voltage and apply the second drive signal Tx2 to the first electrode ELt. The first voltage corresponding to the first drive signal Tx1 and the second voltage corresponding to the second drive signal Tx2 may be determined according to the boosting degree of the charge pump CP relative to the input voltage V.

[0202] In summary, the method for testing a display device according to an embodiment requires: sensing the first mutual capacitance Cm1 when the charge pump CP increases the input voltage V to a first voltage and applies the first drive signal Tx1 to the first electrode ELt; sensing the second mutual capacitance Cm2 when the charge pump CP increases the input voltage V to a second voltage and applies the second drive signal Tx2 to the first electrode ELt; and determining whether a touch operation is performed by detecting the difference between the first mutual capacitance Cm1 and the second mutual capacitance Cm2. In an embodiment, the second voltage corresponding to the second drive signal Tx2 may be less than the first voltage corresponding to the first drive signal Tx1. As described above, when the touch operation is tested by using the charge pump CP built into the signal driving unit 51 instead of directly touching the contact object, the accuracy of the test can be improved and the time required for the test can be shortened.

[0203] Fig.14A is a diagram showing that the first driving signal Tx1 is applied to some of the driving electrode lines and the second driving signal Tx2 is applied to the other driving electrode lines. Fig. 14B Table 1 and Table 2 are shown, Table 1 shows the magnitude of mutual capacitance when the charge pump CP is used without direct touch, and Table 2 shows the magnitude of mutual capacitance in the case of direct hand touch. Fig. 14B In the example, the predetermined test coordinates are (REL2, TEL2).

[0204] wherein the first driving signal Tx1 and the second driving signal Tx2 are applied to a driving electrode line Fig.13 different, Fig.14AIt is shown that the first driving signal Tx1 is applied to some of the driving electrode lines, and the second driving signal Tx2 is applied to some other driving electrode lines. Fig.14A , the charge pump CP can apply the first driving signal Tx1 to some driving electrode lines by increasing the input voltage V received by the signal driving unit 51 to the first voltage, and apply the second driving signal Tx2 to some other driving electrode lines by increasing the input voltage V received by the signal driving unit 51 to the second voltage. The touch integrated circuit TIC can sense the first mutual capacitance Cm1 of the predetermined test coordinates through the first detection signal Rx1 received by the signal detection unit 53, and can sense the second mutual capacitance Cm2 of the predetermined test coordinates through the second detection signal Rx2 received by the signal detection unit 53.

[0205] Fig. 14B A table showing the size of mutual capacitance according to multiple coordinates of multiple driving electrode lines TEL0, TEL1, TEL2, TEL3 and TEL4 and multiple detection electrode lines REL0, REL1, REL2, REL3 and REL4 is shown. Table 1 is data obtained by applying the second drive signal Tx2 to the test drive electrode line TEL2 including the test coordinates (REL2, TEL2) using a charge pump CP, and applying the first drive signal Tx1 to other drive electrode lines TEL0, TEL1, TEL3 and TEL4. In Table 2 showing the data in the case of hand touch, the value of the test coordinate (REL2, TEL2) is 1546, while in Table 1 showing the data obtained by using a charge pump CP, the value of the test coordinate (REL2, TEL2) is 1515. It can be determined that the values ​​of the test coordinates (REL2, TEL2) in Table 1 and Table 2 are very similar to each other.

[0206] According to the above-described embodiments, the method of testing a display device to determine whether a touch detection device operates normally may be performed without directly touching a contact object. However, the scope of one or more embodiments is not limited by these effects.

[0207] It should be understood that the embodiments described herein should be considered to be illustrative only and not for limiting purposes. The description of features or aspects within each embodiment should generally be considered to be applicable to other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, it will be understood by those of ordinary skill in the art that various changes in form and detail may be made therein without departing from the spirit and scope defined by the appended claims.

Claims

1. A method for testing a display device by using a touch sensor and a touch integrated circuit, wherein: The touch sensor includes a driving electrode line and a detecting electrode line, and wherein the touch integrated circuit includes a signal driving unit and a signal detecting unit, and the method includes: sensing a first mutual capacitance of a predetermined test coordinate by applying a first driving signal to the driving electrode line and receiving a detection signal from the detection electrode line; sensing a second mutual capacitance of the predetermined test coordinate by applying a second driving signal to the driving electrode line and receiving a detection signal from the detection electrode line; and Based on a difference between the first mutual capacitance and the second mutual capacitance, it is determined whether a touch operation is performed. 2 . The method of claim 1 , further comprising selecting the second driving signal so that the second mutual capacitance according to the second driving signal has a value corresponding to a mutual capacitance corresponding to a direct touch of a contact object.

3. The method according to claim 1, wherein: The signal driving unit comprises: a first switch and a second switch which are selectively turned on and connect the signal driving unit and the driving electrode line to each other; and A test resistor is connected to the driving electrode line through the second switch.

4. The method according to claim 3, further comprising: If the first switch is turned on, the driving signal generated by the signal driving unit is transmitted to the driving electrode line as the first driving signal, and if the second switch is turned on, the driving signal is transmitted to the driving electrode line as the second driving signal. 5 . The method of claim 3 , further comprising selecting a size of the test resistor so that when the second switch is turned on, the second mutual capacitance has a value corresponding to a mutual capacitance when a contact object directly contacts the display device.

6. The method according to claim 3, wherein: The test resistor has a range of 800Ω to 1200Ω.

7. The method according to claim 1, wherein: The signal driving unit includes a charge pump configured to boost an input voltage and output the boosted voltage, and The first driving signal and the second driving signal are adjusted according to a voltage boosting degree of the charge pump.

8. The method according to claim 7, wherein: A second voltage corresponding to the second driving signal is lower than a first voltage corresponding to the first driving signal.

9. The method according to claim 8, wherein: Each of the first voltage and the second voltage has a range of 3V to 6V.

10. The method according to claim 1, wherein: The driving electrode line comprises: driving electrodes arranged in a first direction; and a first connecting electrode connecting the driving electrodes adjacent to each other in the first direction, and The detection electrode line comprises: detection electrodes arranged in a second direction intersecting the first direction; and The second connecting electrode connects the detection electrodes adjacent to each other in the second direction.

11. The method according to claim 10, wherein: Each of the first mutual capacitance and the second mutual capacitance is a capacitance between one of the first connection electrodes and one of the second connection electrodes, the one first connection electrode and the one second connection electrode together defining the predetermined test coordinate.

12. The method according to claim 10, wherein: The driving electrode lines include a plurality of driving electrode lines arranged apart from each other in the second direction, and the detecting electrode lines include a plurality of detecting electrode lines arranged apart from each other in the first direction.

13. A display device, comprising: A touch sensor, comprising a driving electrode line and a detecting electrode line; A touch integrated circuit, comprising a signal driving unit and a signal detecting unit, wherein the signal driving unit applies a driving signal to the driving electrode line, and the signal detecting unit receives a detection signal from the detection electrode line; a control unit, for determining whether a touch is inputted by a change in mutual capacitance between the driving electrode line and the detecting electrode line; a plurality of switches configured to be selectively turned on according to a control signal of the control unit and connect the signal driving unit to the driving electrode line; and a test resistor connected to the driving electrode line through at least one of the plurality of switches, The size of the test resistor is selected so that the mutual capacitance generated when the test resistor is connected to the driving electrode line has a value corresponding to the mutual capacitance generated when the contact object directly contacts the display device.

14. The display device according to claim 13, wherein: The plurality of switches are connected in parallel with each other.

15. The display device according to claim 13, wherein: The test resistor has a range of 800Ω to 1200Ω.

16. The display device according to claim 13, wherein: The plurality of switches include a first switch and a second switch, the second switch connecting the test resistor to the driving electrode line.

17. The display device according to claim 13, wherein: The driving electrode line comprises: A driving electrode unit arranged in a first direction; and a first connecting electrode connecting the driving electrode units adjacent to each other in the first direction, and The detection electrode line comprises: a detection electrode unit arranged in a second direction intersecting the first direction; and The second connection electrode connects the detection electrode units adjacent to each other in the second direction.

18. The display device according to claim 17, wherein: In a plan view, each of the first connection electrodes has at least a portion overlapping one of the second connection electrodes.

19. The display device according to claim 17, wherein: The driving electrode lines include a plurality of driving electrode lines separated from each other in the second direction, and The plurality of driving electrode lines are respectively connected to the plurality of switches.

20. The display device according to claim 13, further comprising: A driving signal line connects the signal driving unit and the driving electrode line to each other; as well as A detection signal line connects the signal detection unit and the detection electrode line to each other.

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