Touch display device and display panel

Abstract

Touch display device and display panel. The present disclosure provides a touch display device, which includes: a display panel, the display panel includes an internal area where a first step is formed between a first touch electrode metal having a first critical dimension and a lower electrode layer, and an edge area having at least one of CD compensation areas, the edge area is located outside the internal area, and a second step is formed between a second touch electrode metal having a second critical dimension greater than the first critical dimension and the lower electrode layer; a touch circuit, the touch circuit senses the presence of a touch or the touch position by using a touch sensing signal received from the touch electrode metal.

Description

Technical Field

[0001] Embodiments of the present disclosure relate to a touch display device, and more particularly, to a touch display device and a display panel capable of having excellent touch sensitivity by compensating for a critical dimension of a touch electrode metal formed in an edge region. Background Art

[0002] With the development of the information society, people's requirements for display devices for displaying images are getting higher and higher. In this regard, various types of display devices, such as liquid crystal display (LCD) devices, plasma display panel (PDP) display devices, and organic light emitting diode (OLED) display devices, have recently become popular.

[0003] Among these display devices, there is a touch display device having a touch-based input structure, which allows a user to easily, intuitively, and conveniently input information or commands by departing from conventional input methods such as buttons, keyboards, and mice.

[0004] Such a touch display device should recognize the presence or absence of a user's touch and accurately detect touch coordinates in order to provide a touch-based input structure.

[0005] To this end, among various touch sensing methods, a capacitance-based touch sensing method is widely used to detect the presence or absence of a touch and touch coordinates based on a change in capacitance formed on a plurality of touch electrodes on a display panel.

[0006] In addition, from a design perspective, the edge region of a display panel has recently been used as an area capable of displaying and touching. Summary of the Invention

[0007] However, due to a reduction in the step between the touch electrode metal and the lower electrode layer caused by the curvature of the display panel in the edge region of the touch display device, there is a problem of reducing touch sensitivity due to an undesired parasitic capacitance.

[0008] Therefore, the inventors of the present disclosure provide a touch display device and a display panel capable of obtaining excellent touch sensitivity by compensating for a critical dimension of a touch electrode metal formed in the edge region of the display panel.

[0009] In addition, the inventors of the present disclosure provide a touch display device and a display panel capable of effectively performing touch sensing by changing the compensation for the critical dimension of a touch electrode metal formed in the edge region of the display panel.

[0010] Problems to be solved according to embodiments of the present disclosure described below are not limited to the above problems, and those skilled in the art will clearly understand other problems not mentioned from the following description.

[0011] A touch display device according to an exemplary embodiment of the present disclosure includes: a display panel composed of an inner region forming a first step between a first touch electrode metal having a first critical dimension and a lower electrode layer, and an edge region having at least one CD compensation region located outside the inner region, where a second step having a second critical dimension greater than the first critical dimension is formed between a second touch electrode metal and the lower electrode layer; and a touch circuit configured to sense the presence or position of a touch using a touch sensing signal received from the touch electrode metal.

[0012] In a touch display device according to an exemplary embodiment of the present disclosure, the first step is maintained at a constant dimension.

[0013] In a touch display device according to an exemplary embodiment of the present disclosure, the lower electrode layer is a cathode of a light-emitting element.

[0014] In a touch display device according to an exemplary embodiment of the present disclosure, the value of the second critical dimension is greater than the value of the first critical dimension by a constant gap.

[0015] In a touch display device according to an exemplary embodiment of the present disclosure, the dimension of the second step is smaller than the dimension of the first step and is maintained at a constant value.

[0016] A touch display device according to an exemplary embodiment of the present disclosure further includes a step-down region in which the height of the first step between the first touch electrode metal and the lower electrode layer decreases as it approaches the CD compensation region, and the height of the second step between the second touch electrode metal and the lower electrode layer decreases as it approaches the CD compensation region.

[0017] In a touch display device according to an exemplary embodiment of the present disclosure, when the step-down region is formed as multiple regions, the step-down rates of the step-down regions are the same or different.

[0018] In a touch display device according to an exemplary embodiment of the present disclosure, when the CD compensation region is formed as multiple regions, the first critical dimension of the first touch electrode metal and the second critical dimension of the second touch electrode metal formed in the CD compensation region increase as the distance from the inner region increases.

[0019] In a touch display device according to an exemplary embodiment of the present disclosure, the first critical dimension of the first touch electrode metal and the second critical dimension of the second touch electrode metal formed in the CD compensation region increase at a constant ratio as the distance from the inner region increases.

[0020] A display panel according to an exemplary embodiment of the present disclosure includes: an inner region that forms a first step between a first touch electrode metal and a lower electrode layer having a first critical dimension; and an edge region having at least one in a CD compensation region outside the inner region, and a second step having a second critical dimension greater than the first critical dimension is formed between a second touch electrode metal and the lower electrode layer.

[0021] According to an embodiment of the present disclosure, excellent touch sensitivity can be obtained by CD compensation of the edge region of the display panel.

[0022] In addition, according to an embodiment of the present disclosure, there is an effect that touch can be effectively sensed by making various modifications to the CD compensation of the edge region of the display panel.

[0023] The advantages of the embodiments of the present disclosure are not limited to the above advantages. The embodiments of the present disclosure can achieve advantages not mentioned above, and those skilled in the art will clearly understand these advantages from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other objects, features, and advantages of the present disclosure will be more clearly understood from the following detailed description in conjunction with the accompanying drawings, wherein:

[0025] Figure 1 is a diagram schematically showing a touch display device according to an embodiment of the present disclosure;

[0026] Figure 2 is a diagram showing a region where touch electrodes are provided in a display panel according to an embodiment of the present disclosure;

[0027] Figure 3 is an exemplary diagram showing a cross-section of a display panel in a touch display device;

[0028] Figure 4 is a cross-sectional diagram schematically showing steps between a touch electrode metal and a lower electrode layer in an inner region and an edge region of a touch display device;

[0029] Figure 5 is a diagram showing capacitance changes caused by steps between a touch electrode metal and a lower electrode layer in an inner region and an edge region of a touch display device;

[0030] Figure 6 is a diagram schematically showing a display panel according to an embodiment of the present disclosure;

[0031] Figure 7is a cross-sectional view schematically showing a critical dimension of a touch electrode metal according to a step between the touch electrode metal and a lower electrode layer in an inner region and an edge region of a display panel according to an embodiment of the present disclosure;

[0032] Figure 8 is a view showing a case where a CD compensation region is formed into a plurality of regions in a display panel according to an embodiment of the present disclosure;

[0033] Figure 9 is a cross-sectional view schematically showing a step between a touch electrode metal and a lower electrode layer when a CD compensation region is formed into a plurality of regions in a display panel according to an embodiment of the present disclosure;

[0034] Figure 10 is a view showing a capacitance varying according to a step between a touch electrode metal and a lower electrode layer in an inner region and an edge region of a touch display device according to an embodiment of the present disclosure;

[0035] Figure 11 is a view showing a capacitance varying according to a step between a touch electrode metal and a lower electrode layer in eight edge regions of a touch display device according to an embodiment of the present disclosure. Detailed Embodiments

[0036] Advantages and features of the present disclosure and methods for achieving these advantages or features will be apparent from the embodiments described in detail below with reference to the accompanying drawings. However, the present disclosure is not limited to the embodiments, but may be modified in various forms. The embodiments are provided only to complete the disclosure of the present disclosure and to fully inform those skilled in the art of the scope of the present disclosure. The scope of the present disclosure is defined only by the appended claims.

[0037] Shapes, dimensions, ratios, angles, numbers, etc. shown in the drawings provided to illustrate the embodiments of the present disclosure are exemplary, and thus the present disclosure is not limited to the details shown. In the following description, the same elements are denoted by the same reference numerals. When a detailed description of related known functions or configurations involved in the present disclosure makes the gist of the present disclosure unclear, its detailed description will not be given. When the specification mentions "comprising", "having", "configured", etc., another element may be added unless "only" is used. Unless otherwise specified, a singular expression of an element includes two or more elements.

[0038] When constructing elements in the embodiments of the present disclosure, an error range is included even if not explicitly described.

[0039] For example, when using descriptions such as "on", "above", "under", "next to", etc. to describe the positional relationship between two components, unless "only" or "directly" is used, one or more other components may be disposed between the two components.

[0040] When describing a time relationship, for example, when using "after", "subsequently", "then", and "before" to describe the time sequence, unless "only" or "directly" is used, discontinuous cases may be included.

[0041] When describing a signal transmission relationship, for example, when "a signal is sent from node A to node B", unless "only" or "directly" is used, cases where the signal is sent from node A to node B via another node may be included.

[0042] It should be understood that although terms such as "first", "second", etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element, without departing from the scope of the present disclosure.

[0043] The features of the embodiments of the present disclosure may be coupled or combined with each other, or may be separated from each other partially or wholly, and may be interconnected and driven technically in various forms. These embodiments may be implemented independently or in combination.

[0044] Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0045] Figure 1 is a diagram schematically showing a touch display device according to an embodiment of the present disclosure.

[0046] Referring to Figure 1 , a touch display device 100 according to an exemplary embodiment of the present disclosure may provide an image display function for displaying an image and a touch sensing function for sensing a user's touch.

[0047] The touch display device 100 may include a display panel 110 configured to set data lines and gate lines for displaying an image, and a display driving circuit for driving the display panel 110.

[0048] Functionally, the display driving circuit may include a data driving circuit for driving the data lines, a gate driving circuit for driving the gate lines, and a timing controller for controlling the data driving circuit and the gate driving circuit. The display driving circuit may be implemented by one or more integrated circuits.

[0049] The touch display device 100 may include a touch screen panel provided with a plurality of touch electrodes TE for touch sensing, and a touch circuit 130 for driving the touch screen panel and sensing touches.

[0050] The touch screen panel of the touch display device 100 may be an external type that is separately manufactured and bonded to the display panel 110, or may be an embedded type that is manufactured together with the display panel 110 and located within the display panel 110. Hereinafter, it will be assumed that the touch screen panel is embedded in the display panel 110 for description.

[0051] The touch circuit 130 provides a touch driving signal to the display panel 110 to drive the display panel 110, receives a touch sensing signal from the display panel 110, and detects the presence of a touch and the touch coordinates based on the signal.

[0052] The touch circuit 130 may be implemented by including a touch driving circuit that provides a touch driving signal and receives a touch sensing signal, and a touch controller that detects the presence of a touch and the touch coordinates.

[0053] The touch circuit 130 may be implemented as one or more components (e.g., an integrated circuit), or may be separately implemented from the display driving circuit.

[0054] In addition, all or part of the touch circuit 130 may be implemented by integrating with the display driving circuit or its internal circuit. For example, the touch driving circuit of the touch circuit 130 may be implemented as an integrated circuit together with the data driving circuit of the display driving circuit.

[0055] Meanwhile, the touch display device 100 may detect the presence of a touch and the touch coordinates based on the capacitance formed on the touch electrodes TE.

[0056] The touch display device 100 may detect touches using the mutual capacitance method or the self-capacitance method as a capacitance-based touch sensing method.

[0057] In the case of touch sensing based on the mutual capacitance method, the plurality of touch electrodes TE may be composed of driving electrodes and sensing electrodes. The driving electrodes receive a touch driving signal through touch driving lines Tx, and the sensing electrodes send a touch sensing signal through touch sensing lines Rx by forming a capacitance with the driving electrodes. The touch driving lines Tx and the touch sensing lines Rx may be referred to as touch lines.

[0058] Touch sensing based on the mutual capacitance method detects the presence of a touch and the touch coordinates based on a change in the mutual capacitance generated between the driving electrodes and the sensing electrodes according to the presence of a pointer such as a finger or a pen.

[0059] In the case of touch sensing based on the self - capacitance method, each touch electrode TE serves as both a driving electrode and a sensing electrode. That is, a touch driving signal is applied to the touch electrode TE, and a touch sensing signal is sent from the touch electrode TE to which the touch driving signal is applied. Therefore, in touch sensing based on the self - capacitance method, there is no distinction between the driving electrode and the sensing electrode.

[0060] As described above, the touch display device 100 can detect a touch by the mutual - capacitance method or can detect a touch by the self - capacitance method.

[0061] During touch sensing, the touch circuit 130 sequentially outputs touch driving signals to the plurality of touch electrodes TE through the touch driving lines Tx.

[0062] When the user touches the touch display panel 110 while a touch driving signal is applied to the touch electrode TE, the capacitance of the touch electrode TE changes.

[0063] The touch driving lines Tx for sending touch driving signals can be arranged in a direction parallel to the data lines provided on the display panel 110, and the touch sensing lines Rx for sending touch sensing signals can be arranged in a direction parallel to the gate lines provided on the display panel 110.

[0064] Generally, the touch driving lines Tx extend along the long - axis direction of the display panel 110, and the touch sensing lines Rx extend along the short - axis direction of the display panel 110. However, the arrangement of the touch driving lines Tx and the touch sensing lines Rx can be changed according to the shape or structure of the touch display device 100.

[0065] In the case where the display panel 110 performs display driving and touch sensing simultaneously, a touch driving signal can be applied, and touch sensing can be performed while a scan signal is applied to the gate lines provided on the display panel 110.

[0066] Figure 2 It is a diagram showing a region where touch electrodes are provided in a display panel according to an embodiment of the present disclosure.

[0067] Refer to Figure 2 According to an exemplary embodiment of the present disclosure, the region where the touch electrodes TE are provided in the display panel 110 can be divided into an inner region 112 and an edge region 114.

[0068] The inner region 112 is a region of the central portion surrounded by the left - and - right edge regions 114, and can be a region formed in a planar structure. In addition, a plurality of touch electrodes TE having a constant step (height) can be formed in the inner region 112 starting from the lower electrode layer of the display panel 110.

[0069] Therefore, since the height of the step between the touch electrode TE and the lower electrode layer is constant in the inner region 112, the capacitance value according to the position in the inner region 112 can be constant.

[0070] The edge region 114 is a region extending in the vertical direction to the left or right of the inner region 112, and can be formed in a planar structure according to the structure of the display panel 110. However, recently, the edge region 114 is formed in a circular structure with a certain curvature in the latest touch display device 100 having a touch function composed of a streamlined structure.

[0071] Meanwhile, according to the type of the display panel 110, the edge region 114 can be located on the left or right side of the inner region 112, or can be located on the upper or lower side of the inner region 112.

[0072] In this way, since when the edge region 114 is formed in a circular structure, the step height between the touch electrode TE or the touch line and the lower electrode layer gradually decreases as it moves outward from the inner region 112, the capacitance value caused by touch sensing decreases, and thus the touch sensitivity is reduced compared to the inner region 112.

[0073] At this time, the corner regions of the upper edge region 114 or the lower edge region 114 can also be formed in a circular shape and can be included in the edge region 114.

[0074] Figure 3 It is an exemplary diagram showing a cross-section of a display panel in a touch display device.

[0075] Referring to Figure 3 , in the display panel 110 of the touch display device 100, a polyimide (PI) layer L02 is located on the substrate or the backplane L01.

[0076] A buffer layer L03 can be located on the polyimide layer L02, and an interlayer insulating film L04 can be located on the buffer layer L03.

[0077] A gate layer L05 can exist on the interlayer insulating film L04, and gates and the like can be provided at necessary positions on the gate layer L05.

[0078] A gate insulating film L06 can exist on the gate layer L05.

[0079] A source / drain layer L07 can exist on the gate insulating film L06.

[0080] Signal lines such as data lines DL and gate lines GL and the source / drains of a plurality of transistors can be provided on the source / drain layer L07.

[0081] A passivation layer L08 can exist on the source / drain layer L07.

[0082] The planarization layer L09 may be located on the passivation layer L08, and the first electrode layer L10 may be present on the planarization layer L09 at the light-emitting positions corresponding to the sub-pixels.

[0083] A bank layer L11 is provided on the first electrode layer L10, and an organic light-emitting layer L12 is provided on the bank layer L11.

[0084] The second electrode layer L13, which is usually provided in all sub-pixel regions, may be present on the organic light-emitting layer L12.

[0085] The encapsulation layer L14 may be present on the second electrode layer L13 to prevent the penetration of moisture, air, etc.

[0086] The barrier DAM may be present on the peripheral portion of the display panel 110.

[0087] The encapsulation layer L14 may be a single layer or two or more layers.

[0088] In addition, the encapsulation layer L14 may be a composite layer composed of one or more organic material layers and one or more inorganic material layers.

[0089] Here, the encapsulation layer L14 is shown as a multi-layer composed of a first encapsulation layer L14a, a second encapsulation layer L14b, and a third encapsulation layer L14c.

[0090] Each of the first encapsulation layer L14a, the second encapsulation layer L14b, and the third encapsulation layer L14c may be composed of an organic material layer and an inorganic material layer.

[0091] The touch electrode TE and the touch line TL are provided on the encapsulation layer L14.

[0092] The touch electrode TE may be formed as a plate structure without an opening area, or may be formed as a mesh structure. The touch electrode TE of the mesh structure is formed as a touch electrode metal TEM patterned in a mesh pattern, so that a plurality of opening areas can be formed.

[0093] The touch line TL electrically connected to the corresponding touch electrode TE on the encapsulation layer L14 extends to the area without the touch electrode TE to avoid overlapping with the touch electrode TE.

[0094] The touch line TL bypasses the area where the barrier DAM is provided and extends to the area outside the barrier DAM, that is, the portion adjacent to the integrated pad IP.

[0095] In addition, in the area outside the barrier DAM, the touch line TL may be connected to the data line DL on the source / drain layer L07 through the contact hole CNT.

[0096] The data line DL is electrically connected to the integrated pad IP in the region outside the barrier DAM.

[0097] The touch line TL and the touch electrode TE can be on the same layer or different layers while being located on the encapsulation layer L14.

[0098] The encapsulation layer L14 can have a predetermined thickness Tencap in the internal region 112 and can affect the time delay and touch sensitivity during the touch driving process and the touch sensing process.

[0099] Therefore, the thickness Tencap of the encapsulation layer L14 must be designed considering the time delay and touch sensitivity caused by touch driving.

[0100] As described above, the display panel 110 according to the embodiment can have a touch encapsulation (TOE) structure in which the touch electrode metal TEM and the touch line TL are located on the encapsulation layer L14.

[0101] In addition, in this structure of the display panel 110, the height of the step between the touch electrode TE formed on the encapsulation layer L14 and the second electrode layer L13 corresponding to the cathode of the light-emitting element decreases in the direction toward the circular edge region 114.

[0102] This reduction in the height of the step between the touch electrode TE and the lower second electrode layer L13 may result in a capacitance value in the edge region 114 being lower than that in the planar internal region 112, thereby possibly reducing the touch sensitivity.

[0103] Figure 4 is a cross-sectional view schematically showing the step between the touch electrode metal and the lower electrode layer in the internal region and the edge region of the touch display device, Figure 5 is a diagram showing the capacitance change caused by the step between the touch electrode metal and the lower electrode layer in the internal region and the edge region of the touch display device.

[0104] Referring to Figure 4 and Figure 5 , in the touch display device 100 in which the corner region is formed in a circular shape, the internal region 112 is formed in a flat structure such that the height of the step between the lower electrode layer corresponding to the cathode and the touch electrode metal TEM is almost constant. However, as the distance from the internal region 112 increases, the height of the step between the lower electrode layer and the touch electrode metal TEM in the edge region 114 rapidly decreases.

[0105] Therefore, due to the step Step between the lower electrode layer and the touch electrode metal TEM, the parasitic capacitance Cp formed between the lower electrode layer and the touch electrode metal TEM rapidly increases.

[0106] At this time, as the height of the step Step between the lower electrode layer and the touch electrode metal TEM decreases, the parasitic capacitance Cp formed between the lower electrode layer and the touch electrode metal TEM increases. If the increased parasitic capacitance Cp in the edge region 114 exceeds the maximum allowable range Max Spec for touch sensing, the touch sensing operation may not be correctly performed in the edge region 114.

[0107] Therefore, the structure needs to compensate for the increase in the parasitic capacitance Cp by reducing the step Step between the touch electrode metal TEM and the lower electrode layer in the edge region 114 of the touch display device 100.

[0108] The inventors of the present disclosure provide a CD compensation region that can compensate for the capacitance change caused by the decrease in the height of the step between the touch electrode metal TEM and the lower electrode layer in the edge region 114 of the touch display device 100, thereby enabling excellent touch sensitivity to be obtained.

[0109] Figure 6 It is a diagram schematically showing a display panel according to an embodiment of the present disclosure.

[0110] Refer to Figure 6 , according to an exemplary embodiment of the present disclosure, the region where the touch electrode metal TEM is provided in the display panel 110 can be divided into an inner region 112 and an edge region 114.

[0111] The inner region 112 is a region of the central portion surrounded by the left and right edge regions 114 and is a region formed by a planar structure.

[0112] Since the thickness of the encapsulation layer Encap formed between the touch electrode metal TEM and the lower electrode layer is substantially constant in the inner region 112, the critical dimension (CD) of the touch electrode metal TEM corresponding to the line width of the touch electrode metal TEM in the inner region 112 can be formed to have a constant reference critical dimension Ref.

[0113] Meanwhile, the edge region 114 is a circularly formed region extending in the left or right direction and the up or down direction of the inner region 112, and is a region where the step height of the encapsulation layer Encap formed between the touch electrode metal TEM and the lower electrode layer decreases in the outer direction away from the inner region 112.

[0114] At this time, as described above, when the step Step between the touch electrode metal TEM and the lower electrode layer decreases, the parasitic capacitance Cp increases, thereby reducing the touch sensitivity.

[0115] Therefore, some regions in the edge region 114 are formed as the CD compensation region Area2, and the critical dimension CD2 of the touch electrode metal TEM located in the CD compensation region Area2 is formed to be larger than the critical dimension CD1 of the touch electrode metal TEM located in the inner region 112. Therefore, an increase in the parasitic capacitance Cp can be prevented, and the touch sensitivity can be improved.

[0116] For example, the edge region 114 can be divided into a step-down region Area1 and a CD compensation region Area2.

[0117] The step-down region Area1 is a region formed at a position adjacent to the inner region 112 in the edge region 114, and is a region that reduces the height of the step Step between the touch electrode metal TEM and the lower electrode layer by the circular shape of the edge region 114.

[0118] On the other hand, the CD compensation region Area2 is a region having a constant width starting from the end of the step-down region Area1. The critical dimension CD2 of the touch electrode metal TEM formed in the CD compensation region Area2 is larger than the critical dimension CD1 of the touch electrode metal TEM formed in the inner region 112 by a constant gap Gap.

[0119] In this case, the CD compensation region Area2 can be a region where the step Step2 between the touch electrode metal TEM and the lower electrode layer has a constant value.

[0120] Since the critical dimension CD2 of the touch electrode metal TEM formed in the CD compensation region Area2 is larger than the critical dimension CD1 of the touch electrode metal TEM formed in the inner region 112, an increase in the parasitic capacitance Cp formed between the touch electrode metal TEM in the edge region 114 and the lower electrode layer can be reduced.

[0121] At this time, since the step-down region Area1 is located close to the inner region 112, the value of the critical dimension CD of the touch electrode metal TEM formed in the step-down region Area1 can be the same as the value of the critical dimension CD1 of the touch electrode metal TEM formed in the inner region 112. In this case, it can be considered that the step-down region Area1 is included in the inner region 112.

[0122] On the other hand, since the step-down region Area1 is also adjacent to the CD compensation region Area2, the value of the critical dimension CD of the touch electrode metal TEM formed in the step-down region Area1 can be the same as the value of the critical dimension CD2 of the touch electrode metal TEM formed in the CD compensation region Area2.

[0123] When the value of the critical dimension CD of the touch electrode metal TEM formed in the step-down region Area1 is the same as the value of the critical dimension CD2 of the touch electrode metal TEM formed in the CD compensation region Area2, it can be considered that the step-down region Area1 is included in the CD compensation region Area2.

[0124] According to the type of the display panel 110, such a CD compensation region Area2 can be formed in the edge region 114 located on the left or right side of the display panel 110, or formed in the upper edge region 114 or the lower edge region 114.

[0125] Figure 7 A cross-sectional view schematically showing the critical dimension of the touch electrode metal according to the step between the touch electrode metal and the lower electrode layer in the internal region and the edge region of the display panel according to an embodiment of the present disclosure.

[0126] Refer to Figure 7 , the internal region 112 in the display panel 110 according to an embodiment of the present disclosure may have a step Step1 with a constant height, and the constant height of the step Step1 is equal to the thickness of the encapsulation layer Encap formed between the touch electrode metal TEM and the lower electrode layer.

[0127] Since the edge region 114 has a circular curvature, the region adjacent to the internal region 112 in the edge region 114 corresponds to the step-down region Area1, and in this step-down region Area1, the step between the touch electrode metal TEM and the lower electrode layer decreases at a constant ratio.

[0128] The width of the step-down region Area1 may vary according to the size or structure of the display panel 110.

[0129] The CD compensation region Area2 is formed starting from a point at the end of the step-down region Area1 having a constant width, and in the CD compensation region Area2, the step Step2 between the touch electrode metal TEM and the lower electrode layer is constant.

[0130] To prevent an increase in the parasitic capacitance Cp caused by a decrease in the height of the step Step2 between the touch electrode metal TEM and the lower electrode layer, the critical dimension CD2 of the touch electrode metal TEM in the CD compensation region Area2 is formed to be larger than the critical dimension CD1 of the touch electrode metal TEM in the internal region 112.

[0131] In the CD compensation region Area2, the height of the step Step2 between the touch electrode metal TEM and the lower electrode layer may be smaller than the height of the step Step1 in the internal region 112.

[0132] The step Step2 in the CD compensation area Area2 can vary according to the width of the step-down area Area1 and the step-down rate in the step-down area Area1.

[0133] When forming the CD compensation area Are2 within the edge area 114, an increase in the parasitic capacitance Cp occurring in the circular edge area 114 can be suppressed.

[0134] The CD compensation area Area2 can be formed as one area or can be formed as multiple areas within the edge area 114.

[0135] Figure 8 is a diagram showing a case where the CD compensation area is formed as multiple areas in a display panel according to an embodiment of the present disclosure. Figure 9 is a cross-sectional view schematically showing a step between a touch electrode metal and a lower electrode layer when the CD compensation area is formed as multiple areas in a display panel according to an embodiment of the present disclosure.

[0136] Referring to Figure 8 and Figure 9 According to an exemplary embodiment of the present disclosure, the area where the touch electrode metal TEM is disposed in the display panel 110 can be divided into an inner area 112 and an edge area 114.

[0137] The inner area 112 is an area of the central part surrounded by the left and right edge areas 114 and is formed of a planar structure. The critical dimension CD1 of the touch electrode metal TEM formed in the inner area 112 can have a constant reference critical dimension Ref.

[0138] Meanwhile, the edge area 114 is an area that extends in the left or right, up or down direction of the inner area 112 and forms a circle. In the edge area 114, the step Step between the touch electrode metal TEM and the lower electrode layer decreases in the outer direction away from the inner area 112.

[0139] In this case, by forming multiple CD compensation areas in the edge area 114, an increase in the parasitic capacitance Cp can be prevented and the touch sensitivity can be improved.

[0140] For example, the edge area 114 can be divided into multiple step-down areas Area1, step-down area Area3, and multiple CD compensation areas Area2, CD compensation area Area4.

[0141] In this case, the step-down area Area1 is an area where the height of the step between the touch electrode metal TEM and the lower electrode layer decreases uniformly due to the circle of the edge area 114 within the edge area 114.

[0142] On the other hand, the CD compensation regions Area2 and Area4 are regions with a constant width starting from the endpoints of the stepped-down regions Area1 and Area3. In the CD compensation regions Area2 and Area4, the steps Step2 and Step3 between the touch electrode metal TEM and the lower electrode layer are respectively maintained at constant values, but the critical dimensions CD2 and CD3 of the touch electrode metal TEM gradually increase as the distance from the internal region 112 increases.

[0143] At this time, the CD compensation regions Area2 and Area4 can be alternately formed adjacent to the stepped-down regions Area1 and Area3 respectively.

[0144] For example, the first CD compensation region Area2 is formed at a position adjacent to the first stepped-down region Area1, and the step Step2 between the touch electrode metal TEM and the lower electrode layer in it is smaller than the step Step2 between the touch electrode metal TEM and the lower electrode layer in the internal region 112.

[0145] The second stepped-down region Area3 is formed starting from the endpoint of the first CD compensation region Area2 where the critical dimension CD2 of the touch electrode metal TEM is constant. In the second stepped-down region Area3, the height of the step between the touch electrode metal TEM and the lower electrode layer decreases again.

[0146] The step-down rate of the second stepped-down region Area3 can be the same as or different from the step-down rate of the first stepped-down region Area1.

[0147] The second CD compensation region Area4 can be formed with a constant width starting from the endpoint of the second stepped-down region Area3. In the second CD compensation region Area4, the critical dimension CD3 of the touch electrode metal TEM in the first CD compensation region Area2 can be larger than the critical dimension CD2 of the touch electrode metal TEM.

[0148] The gap Gap between the critical dimension CD3 of the touch electrode metal TEM formed in the second CD compensation region Area4 and the critical dimension CD2 of the touch electrode metal TEM formed in the first CD compensation region Area2 can be the same as or different from the gap between the critical dimension CD2 of the touch electrode metal TEM formed in the first CD compensation region Area2 and the critical dimension CD1 of the touch electrode metal TEM formed in the internal region 112.

[0149] That is to say, the critical dimension CD of the touch electrode metal TEM formed in the CD compensation regions Area2 and Area4 can increase at a constant rate or at different rates as the distance from the internal region 112 increases.

[0150] As described above, when forming a plurality of CD compensation regions Area2 and Area4 within the edge region 114, the increase in the parasitic capacitance Cp formed by the step Step1 between the touch electrode metal TEM and the lower electrode layer in the edge region 114 can be gradually reduced, thereby effectively preventing the decrease in touch sensitivity caused by the parasitic capacitance Cp.

[0151] Figure 10 It is a diagram showing that in the internal region and the edge region of a touch display device according to an embodiment of the present disclosure, the capacitance changes according to the step between the touch electrode metal and the lower electrode layer.

[0152] Refer to Figure 10 , in the edge region 114 of the touch display device 100 according to an exemplary embodiment of the present disclosure, when forming a CD compensation region, it can be seen that the parasitic capacitance Cp formed between the touch electrode metal TEM and the lower electrode layer is reduced in the edge region 114.

[0153] Compared with the case 150 where no CD compensation region is formed and the critical dimension of the touch electrode metal TEM remains unchanged, the increase in the parasitic capacitance Cp in the edge region 114 can be suppressed and the touch sensitivity in the edge region 114 can be improved.

[0154] The CD compensation region can be applied to all edge regions 114 including the corner region and the left or right side, upper or lower side of the display panel 110.

[0155] Figure 11 It is a diagram showing that in the eight edge regions of a touch display device according to an embodiment of the present disclosure, the capacitance changes according to the step between the touch electrode metal and the lower electrode layer.

[0156] Refer to Figure 11 , the CD compensation region in the touch display device 100 according to an exemplary embodiment of the present disclosure can be formed in all edge regions 114 including the left or right side, upper or lower side and the corner region of the display panel 110.

[0157] In this way, in the case 160 where a CD compensation region is formed in the edge region 114, the parasitic capacitance Cp formed between the touch electrode metal TEM and the lower electrode layer in the edge region 114 is reduced. Therefore, compared with the case 150 where no CD compensation region is formed and the same critical dimension CD of the touch electrode metal TEM is formed, the increase in the parasitic capacitance Cp in the edge region 114 can be suppressed.

[0158] The above description merely illustrates the technical idea of the present disclosure. Those skilled in the art can make various modifications and changes without departing from the basic features of the present disclosure, such as combination, separation, substitution, and change of configuration. Therefore, the embodiments of the present disclosure do not limit the technical idea of the present disclosure, but explain the technical idea of the present disclosure. The technical idea of the present disclosure is not limited to the embodiments. The scope of the present disclosure is defined by the appended claims, and all technical ideas within the scope equivalent to the present disclosure should be understood to fall within the scope of the present disclosure.

[0159] Cross-reference to related applications

[0160] This application claims priority to Korean Patent Application No. 10-2019-0149792, filed on November 20, 2019, which is hereby incorporated by reference in its entirety for all purposes as if fully set forth herein.

Claims

1. A touch display device, comprising: A display panel, the display panel including an internal region having a first step between a lower electrode layer forming a light-emitting element and a first touch electrode metal having a first critical dimension, and an edge region having at least one critical dimension CD compensation region located outside the internal region, the edge region forming a second step between the lower electrode layer and a second touch electrode metal having a second critical dimension greater than the first critical dimension, the first critical dimension and the second critical dimension being the line widths of the first touch electrode metal and the second touch electrode metal, respectively; And A touch circuit, the touch circuit sensing the presence or position of a touch by using touch sensing signals received from the first touch electrode metal and the second touch electrode metal, Wherein, the size of the second step is smaller than the size of the first step and remains at a constant value.

2. The touch display device according to claim 1, wherein, The first step remains at a constant size.

3. The touch display device according to claim 1, wherein, The lower electrode layer is the cathode of the light-emitting element.

4. The touch display device according to claim 1, wherein, The value of the second critical dimension is greater than the value of the first critical dimension by a constant gap.

5. The touch display device according to claim 1, the touch display device further comprising: A step-down region, in the step-down region, the height of the first step between the first touch electrode metal and the lower electrode layer decreases as it approaches the CD compensation region, and the height of the step between the third touch electrode metal and the lower electrode layer decreases as it approaches the CD compensation region.

6. The touch display device according to claim 5, wherein, When the step-down region is formed into multiple regions, the step-down rates of the step-down region are the same or different.

7. The touch display device according to claim 1, wherein, When the CD compensation region is formed into multiple regions, the first critical dimension of the first touch electrode metal and the second critical dimension of the second touch electrode metal formed in the CD compensation region increase as the distance from the internal region increases.

8. The touch display device according to claim 7, wherein, The first critical dimension of the first touch electrode metal and the second critical dimension of the second touch electrode metal formed in the CD compensation region increase at a constant ratio as the distance from the internal region increases.

9. A display panel, the display panel including: An internal region, the internal region forming a first step between a first touch electrode metal having a first critical dimension and a lower electrode layer of a light-emitting element; And An edge region, the edge region having at least one in a critical dimension CD compensation region located outside the internal region, the edge region forming a second step between the lower electrode layer and a second touch electrode metal having a second critical dimension greater than the first critical dimension, Wherein, the first critical dimension and the second critical dimension are the line widths of the first touch electrode metal and the second touch electrode metal, respectively, and Wherein, the size of the second step is smaller than the size of the first step and remains at a constant value.

10. The display panel according to claim 9, wherein, The first step remains at a constant size.

11. The display panel according to claim 9, wherein, The lower electrode layer is the cathode of the light-emitting element.

12. The display panel according to claim 9, wherein, The value of the second critical dimension is greater than the value of the first critical dimension by a constant gap.

13. The display panel according to claim 9, the display panel further comprising: A step-down region, in which the height of the first step between the first touch electrode metal and the lower electrode layer decreases as it approaches the CD compensation region, and the height of the step between the third touch electrode metal and the lower electrode layer decreases as it approaches the CD compensation region.

14. The display panel according to claim 13, wherein, When the step-down region is formed into a plurality of regions, the step-down rates of the step-down regions are the same or different.

15. The display panel according to claim 9, wherein, When the CD compensation region is formed into a plurality of regions, the first critical dimension of the first touch electrode metal and the second critical dimension of the second touch electrode metal formed in the CD compensation region increase as the distance from the internal region increases.

16. The display panel according to claim 15, wherein, The first critical dimension of the first touch electrode metal and the second critical dimension of the second touch electrode metal formed in the CD compensation region increase at a constant rate as the distance from the internal region increases.

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