Patent Description:
A display device is a device for displaying an image, and generally includes a display panel such as an organic light emitting display panel or a liquid crystal display panel.

A mobile electronic device generally includes a display device to provide an image to a user. The proportion of mobile electronic devices having a larger display screen while having the same or smaller volume or thickness than conventional mobile electronic devices is increasing, and foldable display devices or bendable display devices, such as those structured to be folded and unfolded in order to provide a larger screen only when used, are also being developed.

Meanwhile, as a gap between a display panel of a display device and a surrounding set structure becomes narrow, static electricity introduced from the outside may cause a failure of the display device. In particular, when there is an insufficient bypass path of the static electricity introduced from the outside, the static electricity may flow to a driving chip and/or driving wirings around the driving chip, thereby causing a driving failure of the display device.

In addition, applying a thick structure or cover may be considered to prevent introduction of static electricity to the driving chip and the driving wirings around the driving chip. However, due to miniaturization of display devices, it may not be practical to apply an additional structure to protect the driving chip and the driving wirings around the driving chip.

<CIT> discloses display device including a display panel for displaying an image on a front surface of the display panel; a touch sensing unit provided on the display panel to sense a touch; an insulating film covering the touch sensing unit; a first circuit board of which one end is connected to the touch sensing unit; and a polarizing layer covering the touch sensing unit and a portion of the first circuit board.

The invention provides a flexible display panel as claimed in claim <NUM>.

Embodiments of the present disclosure may provide a display device having a robust display screen resistant to external electromagnetic stress, such as, for example, an electromagnetic pulse or static electricity. However, aspects of the present disclosure are not restricted to the ones set forth herein. The above and other aspects of the present disclosure will become more apparent to those of ordinary skill in the pertinent art to which the present disclosure pertains by referencing the detailed description of the present disclosure given below.

These and/or other aspects may become more apparent and more readily appreciated from the following description of embodiments, when taken in conjunction with the accompanying drawings, in which:.

Embodiments of the present disclosure and methods of accomplishing the same may be understood more readily by reference to the following detailed description of embodiments and the accompanying drawings. The present disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concept of the invention to those skilled in the art, where the scope of the present disclosure is defined by the appended claims.

It will be understood that when an element or layer is referred to as being "on" another element or layer, the element or layer can be directly on another element or layer or on intervening elements or layers. Like numbers may refer to like elements throughout the specification.

A display device may be used for displaying moving images or still images. The display device may be used as a display screen in portable electronic devices such as mobile phones, smartphones, tablet personal computers (PCs), smart watches, watch phones, mobile communications terminals, electronic notebooks, electronic books, portable multimedia players (PMPs), navigation systems and ultra-mobile PCs (UMPCs), as well as in various products such as televisions, notebook computers, monitors, billboards and the Internet of things (IoT). Hereinafter, embodiments will be described with reference to the attached drawings.

<FIG> illustrates a plan layout view of a display device <NUM> according to an embodiment in a first operating or unfolded state. <FIG> illustrates a cross-sectional view of a display panel <NUM> of <FIG> in a second operating or folded state.

Referring to <FIG> and <FIG>, the display device <NUM> may display a screen or an image through a display area DA and may be any device including the display area DA. Examples of the display device <NUM> may include, but are not limited to, a smartphone, a mobile phone, a tablet PC, a personal digital assistant (PDA), a PMP, a television, a game machine, a wristwatch-type electronic device, a head mounted display, a monitor of a PC, a notebook computer, a car navigation system, a car dashboard, a digital camera, a camcorder, an external billboard, an electronic board, various medical devices, various examination devices, various home appliances including the display area DA, such as a refrigerator and a washing machine, and IoT devices. A representative example of a foldable display device to be described later may be, but is not limited to, a foldable smartphone, a foldable tablet PC, or a foldable notebook computer.

The display device <NUM> may be substantially rectangular in plan view. The display device <NUM> may be shaped like a rectangle with right-angled corners or a rectangle with rounded corners in plan view. The display device <NUM> shaped like a rectangle with rounded corners in plan view will be mainly described below. The display device <NUM> may include four sides or edges. The display device <NUM> may include long sides and short sides. The display device may have any shape in plan view, without limitation. For example, an alternate embodiment display device may be substantially trigonal, hexagonal, octagonal, or circular in plan view.

The short sides of the display device <NUM> may extend along a direction, and the long sides of the display device <NUM> may extend along another direction. For example, the short sides may extend along a first direction DR1, and the long sides may extend along a second direction DR2. In embodiments, the first direction DR1 and the second direction DR2 intersect each other in different directions. In the plan view of <FIG>, the first direction DR1 is defined as a horizontal direction, and the second direction DR2 is defined as a vertical direction for ease of description. In the following embodiments, a first side of the first direction DR1 refers to a right direction in plan view, a second side of the first direction DR1 refers to a left direction in plan view, a first side of the second direction DR2 refers to an upper direction in plan view, and a second side of the second direction DR2 refers to a lower direction in plan view. However, directions mentioned in embodiments should be understood as relative directions, and the embodiments are not limited to the mentioned directions.

The display device <NUM> may include the display panel <NUM> displaying an image, an external device attached to the display panel <NUM>, and a cover member <NUM> covering the external device. The external device includes a driving chip <NUM> and a printed circuit film <NUM> spaced apart from the driving chip <NUM> along the second direction DR2. The cover member <NUM> may completely cover the driving chip <NUM> and partially cover the printed circuit film <NUM>.

The display panel <NUM> is a panel that displays a screen or an image. Examples of the display panel <NUM> may include a self-luminous display panel such as an organic light emitting display (OLED) panel, an inorganic electroluminescent (EL) display panel, a quantum dot light emitting display (QED) panel, a micro-light emitting diode (LED) display panel, a nano-LED display panel, a plasma display panel (PDP), a field emission display (FED) panel or a cathode ray tube (CRT) display panel and a light receiving display panel such as a liquid crystal display (LCD) panel or an electrophoretic display (EPD) panel. An OLED panel will hereinafter be described as an example of the display panel <NUM>. The OLED panel applied to embodiments will be simply referred to as the display panel <NUM> unless a particular distinction is described. However, embodiments are not limited to the OLED panel, and other display panels listed above or known in the art are also applicable within the scope of the present disclosure.

The display panel <NUM> may include a first surface and a second surface. In the display device <NUM>, a direction from the second surface toward the first surface of the display panel <NUM> may be a display direction, and a direction from the first surface toward the second surface may be a non-display direction. However, embodiments are not limited to this case, and both the direction from the second surface toward the first surface of the display panel <NUM> and the direction from the first surface toward the second surface may also be display directions.

The display device <NUM> may be a foldable device. The term "foldable device," as used herein, refers to a device that can be folded and is used to mean not only a folded device but also a device that can have both a folded state and an unfolded state. In addition, when a device is folded, it typically means that the device is folded at an angle of about <NUM> degrees. However, embodiments are not limited to this case. The device may also be understood as being folded even when the folding angle is greater or less than <NUM> degrees, for example, <NUM> to less than <NUM> degrees or <NUM> to less than <NUM> degrees. Furthermore, the device may be referred to as being in the folded state when it is folded out of the unfolded state although it is not completely folded to its maximum folding angle (e.g., <NUM> degrees). For example, even when the device is folded at an angle of <NUM> degrees or less, it may be expressed as being in the folded state to distinguish its state from the unfolded state as long as the maximum folding angle is <NUM> degrees or more. When the device is folded, a radius of curvature may be, but is not limited to, <NUM> or less, preferably in the range of <NUM> to <NUM>, or about <NUM>.

Hereinafter, the folded state described above may be referred to as the first operating state, and the unfolded state described above may be referred to as the second operating state.

A folding area FA, such as at a folding axis, and non-folding areas NFA1 and NFA2, such as away from the folding axis, may be defined in the display panel <NUM>.

As illustrated in <FIG>, the display panel <NUM> may be folded based on the folding area FA, or the folding axis, in the second operating state.

The folding area FA may have a linear shape extending along the first direction DR1 in plan view. Although the folding area FA extends parallel to the short sides of the display device <NUM> in the drawings, embodiments are not limited to this case. The folding area FA may also be parallel to the long sides or inclined with respect to the short sides and the long sides.

In an embodiment, the folding area FA of the display device <NUM> may be set at a specific position. In the display device <NUM>, the number of the folding areas FA set at specific positions may be one or two or more. In an embodiment, the position of the folding area FA in the display device <NUM> need not be fixed but may be freely set in various areas.

A first non-folding area NFA1 may be located on a first side of the folding area FA in the second direction DR2, and a second non-folding area NFA2 may be located on a second side of the folding area FA in the second direction DR2. When the folding area FA is set at a specific position, the first non-folding area NFA1 and the second non-folding area NFA2 may be set as areas that are not folded.

The display panel <NUM> may, in plan view, be divided into the display area DA displaying an image and a non-display area NDA disposed around the display area DA, according to whether an image is displayed.

The display area DA may include a plurality of pixels. Each of the pixels is a basic unit for displaying a screen. The pixels may include, but are not limited to, red pixels, green pixels, and blue pixels. The pixels may further include white pixels. The pixels may be alternately arranged in plan view. For example, the pixels may be arranged in a matrix direction.

The non-display area NDA may be disposed around the display area DA. The non-display area NDA may surround the display area DA. In an embodiment, the display area DA may be rectangular, and the non-display area NDA may be disposed around four sides of the display area DA.

The rectangular shape of the display area DA may include, for example, short sides extending along the first direction DR1 and long sides extending along the second direction DR2. The non-display area NDA may be disposed around the short sides and the long sides of the display area DA. A black matrix may be disposed on the non-display area NDA of the display panel <NUM> to prevent leakage of light emitted from adjacent pixels.

The display area DA of the display panel <NUM> may be disposed over both the first non-folding area NFA1 and the second non-folding area NFA2. Furthermore, the display area DA may be located in the folding area FA corresponding to a boundary between the first non-folding area NFA1 and the second non-folding area NFA2. That is, the display area DA of the display device <NUM> may be continuously disposed regardless of boundaries between the non-folding areas NFA1 and NFA2 and the folding area FA. However, embodiments are not limited to this case, and the display area DA may also be disposed in the first non-folding area NFA1 but need not be disposed in the second non-folding area NFA2. Alternatively, the display area DA may be disposed in the first non-folding area NFA1 and the second non-folding area NFA2 but need not be disposed in the folding area FA.

Like the display area DA, the non-display area NDA may be located in the first non-folding area NFA1, the second non-folding area NFA2, and the folding area FA.

Referring to <FIG>, in the second operating state, the display device <NUM> may be in-folded such that parts of the first surface of the display panel <NUM> face each other. In the second operating state, the display device <NUM> may be folded such that a surface of the first non-folding area NFA1 of the display panel <NUM> faces a surface of the second non-folding area NFA2.

In some embodiments, the display device <NUM> may be out-folded such that parts of the second surface of the display panel <NUM> face each other. The display device <NUM> might be only in-folded or out-folded or may be both in-folded and out-folded. The display device <NUM> that can be both in-folded and out-folded may be in-folded and out-folded based on the same folding area FA or may include a plurality of folding areas FA that are folded differently based on an in-folding line or axis and an out-folding line or axis.

The non-display area NDA disposed around the long sides and the short sides of the display area DA may have, for example, a substantially quadrilateral frame shape with rounded corners in plan view. A quadrilateral frame shape with rounded corners may be formed by an outer profile of the display area DA, first and second outer profiles (where the first outer profile is adjacent to a long side of the display area DA on the second side of the first direction DR1, and the second outer profile is opposite the first outer profile) of the non-display area NDA which are adjacent to the long sides of the display area DA and extend along the second direction DR2, a third outer profile of the non-display area NDA which is adjacent to a short side of the display area DA on the first side of the second direction DR2 and extends along the first direction DR1, a fourth outer profile of the non-display area NDA which is adjacent to a short side of the display area DA on the second side of the second direction DR2 and extends along the first direction DR1, and four curved profiles which connect adjacent outer profiles of the non-display area NDA.

The non-display area NDA adjacent to the short side of the display area DA located on the second side of the second direction DR2 may further include a protruding part which protrudes further outward than the fourth outer profile. A width of the protruding part of the non-display area NDA in the first direction DR1 may be smaller than a width of the fourth outer profile in the first direction DR1. The width of the protruding part of the non-display area NDA in the first direction DR1 may be gradually reduced toward the second side of the second direction DR2, but embodiments are not limited to this case.

The protruding part may include a bending area BA. The bending area BA may have a line shape extending along the first direction DR1. The bending area BA may overlap the fourth outer profile. However, embodiments are not limited to this case, and the bending area BA may also be located closer to the second side of the second direction DR2 than the fourth outer profile. In the bending area BA of the non-display area NDA, the display panel <NUM> may be bent in a thickness direction. The display device <NUM> according to the embodiment may be not only a foldable device but also a bendable device in which the display panel <NUM> can be bent. The display panel <NUM> may be bent based on the bending area BA. When the display device <NUM> is bent, parts of the second surface of the display panel <NUM> may face each other.

The protruding part may be surrounded by a first curved profile connecting the first outer profile and the fourth outer profile, a second curved profile connecting the second outer profile and the fourth outer profile, a fifth outer profile connecting the first curved profile and the second curved profile, and the fourth outer profile. The fifth outer profile may extend along the first direction DR1. Each of the curved profiles may have, but is not limited to, a curved shape protruding inward.

The external device may be attached to a second side of the bending area BA of the protruding part in the second direction DR2. An attachment position of the driving chip <NUM> may be located between an attachment position of the printed circuit film <NUM> and the bending area BA. In the first operating state, the driving chip <NUM> may be located between the printed circuit film <NUM> and the display area DA or between the printed circuit film <NUM> and the bending area BA in plan view.

The driving chip <NUM> may include a driving integrated circuit configured to apply a data voltage to each pixel and control data voltage application and/or scan signal application. A plurality of driving pads may be disposed at the attachment position of the driving chip <NUM> in the non-display area NDA, and the driving chip <NUM> may be attached to the driving pads.

The printed circuit film <NUM> may be configured to provide a data voltage signal and a data voltage application control signal and/or a scan signal application control signal to the driving chip <NUM>. In addition, the printed circuit film <NUM> may be configured to provide a high-voltage potential signal and a low-voltage potential signal to each pixel.

The printed circuit film <NUM> may further include a connector <NUM> located at an end on the second side of the second direction DR2. The connector <NUM> may be connected to a main circuit board.

The cover member <NUM> may be disposed on the driving chip <NUM> and the printed circuit film <NUM>. The cover member <NUM> may overlap the whole of the driving chip <NUM> and part of the printed circuit film <NUM>. The cover member <NUM> may be disposed on the attachment positions of the driving chip <NUM> and the printed circuit film <NUM> on the non-display area NDA of the display panel <NUM>.

<FIG> illustrates a cross-sectional view of the display device <NUM> of <FIG> when unbent. <FIG> illustrates a cross-sectional view of the display device <NUM> of <FIG> when bent. <FIG> illustrates a cross-sectional view of a display panel <NUM> according to an embodiment.

Referring to <FIG>, the display panel <NUM> may include a plurality of elements. For example, the display panel <NUM> may include a substrate <NUM> and a circuit driving layer <NUM> disposed on the substrate <NUM>. The circuit driving layer <NUM> may include a circuit for driving a light emitting layer <NUM> of each pixel. The circuit driving layer <NUM> may include a plurality of thin-film transistors. The light emitting layer <NUM> may be disposed on the circuit driving layer <NUM>. The light emitting layer <NUM> may include an organic light emitting layer. The light emitting layer <NUM> may emit light of various luminance levels according to a driving signal received from the circuit driving layer <NUM>. An encapsulating layer <NUM> may be disposed on the light emitting layer <NUM>. The encapsulating layer <NUM> may include an inorganic layer or a laminate of an inorganic layer and an organic layer. Alternatively, the encapsulating layer <NUM> may be glass or an encapsulating film. A touch layer <NUM> may be disposed on the encapsulating layer <NUM>. The touch layer <NUM> is a layer for recognizing a touch input and may function as a touch member. The touch layer <NUM> may include a plurality of sensing regions and sensing electrodes. A polarizing layer POL may be disposed on the touch layer <NUM>. The polarizing layer POL may reduce reflection of external light. The polarizing layer POL may be attached to the touch layer <NUM> through an adhesive layer. The polarizing layer POL is optional. A protective layer may be disposed on the polarizing layer POL. The protective layer may include, for example, a window member. The protective layer may be attached onto the polarizing layer POL by, e.g., an optically clear adhesive.

In <FIG> and <FIG>, only the substrate <NUM> and the polarizing layer POL disposed on the substrate <NUM> are illustrated by simplifying the cross-sectional structure of the display panel <NUM> for ease of description.

The polarizing layer POL may be disposed on a first surface of the substrate <NUM>. Like the first surface of the display panel <NUM> described above with reference to <FIG> and <FIG>, the first surface of the substrate <NUM> may be an upper surface of the substrate <NUM> in the drawings, and a second surface of the substrate <NUM> may be a surface (a lower surface) opposite the first surface of the substrate <NUM>. The polarizing layer POL may be disposed in the display area DA and may not be disposed in the non-display area NDA.

The display device <NUM> may further include an under-panel sheet <NUM> disposed on the second surface of the substrate <NUM>. The under-panel sheet <NUM> may include a polymer film layer <NUM> and a metal plate <NUM> disposed under the polymer film layer <NUM>.

The polymer film layer <NUM> may include a polymer film. The polymer film layer <NUM> may include, for example, polyimide (PI), polyethylene terephthalate (PET), polycarbonate (PC), polyethylene (PE), polypropylene (PP), polysulfone (PSF), polymethyl methacrylate (PMMA), triacetyl cellulose (TAC), or cyclo olefin polymer (COP). The polymer film layer <NUM> may include a functional layer on at least one surface. The functional layer may include, for example, a light absorbing layer. The light absorbing layer may include a light absorbing material such as a black pigment or dye. The light absorbing layer may be formed on the polymer film by coating or printing black ink.

The metal plate <NUM> dissipates heat generated from the display panel <NUM> or other parts of the display device <NUM>. The metal plate <NUM> may include a metallic plate. The metallic plate may contain a metal with excellent thermal conductivity, such as copper or silver. The metal plate <NUM> may also be a heat dissipating sheet containing graphite or carbon nanotubes.

The metal plate <NUM> may be divided by a folding line as illustrated in <FIG> and <FIG> to facilitate the folding of the display device <NUM>, although embodiments are not limited to this case. For example, a first metal plate may be disposed in the first non-folding area NFA1, and a second metal plate may be disposed in the second non-folding area NFA2. The first metal plate and the second metal plate may be physically separated by the folding line FDA.

The display device <NUM> may further include a bending protection layer BPL. The bending protection layer BPL may be disposed on the first surface of the substrate <NUM> in the bending area BA.

The bending protection layer BPL may alleviate stress applied to a signal line (e.g., a signal line connecting each pixel and a driving pad) passing through the bending area BA, thereby preventing creation of cracks in the signal line.

For example, the bending protection layer BPL may include an organic material. The organic material may include a photosensitive organic material. For example, the bending protection layer BPL may include an acrylic material.

The bending protection layer BPL may extend further toward the display area DA from the bending area BA. The bending protection layer BPL may contact an outer side surface of the polarizing layer POL. However, embodiments are not limited to this case, and the bending protection layer BPL need not contact the outer side surface of the polarizing layer POL.

The driving chip <NUM>, the printed circuit film <NUM> and a step compensation member <NUM> may be disposed on a first side of the bending area BA in the second direction DR2 in the non-display area NDA of the display panel <NUM>. The step compensation member <NUM> may be disposed between the driving chip <NUM> and the bending protection layer BPL, and the driving chip <NUM> may be disposed between the step compensation member <NUM> and the printed circuit film <NUM>. The cover member <NUM> may be disposed on the step compensation member <NUM>, the driving chip <NUM>, and the printed circuit film <NUM>.

A ground voltage may be applied to the printed circuit film <NUM> such as the printed circuit film <NUM> is grounded.

As illustrated in <FIG>, when the display device <NUM> is bent, parts of the second surface of the display panel <NUM> may face each other. Each of the attachment position of the driving chip <NUM> and the attachment position of the printed circuit film <NUM> may overlap the non-display area NDA between the display area DA and the bending area BA of the display panel <NUM> in the thickness direction.

As the display device <NUM> is bent, the printed circuit film <NUM> may be positioned inside the driving chip <NUM> (for example, in a direction toward the display area DA), and conversely, the driving chip <NUM> may be positioned outside the printed circuit film <NUM> (for example, in a direction opposite to the direction toward the display area DA).

When the display device <NUM> is bent, since the driving chip <NUM> is positioned outside the printed circuit film <NUM> (for example, in the direction opposite to the direction toward the display area DA), it may be located on the periphery of the display device <NUM>. The driving chip <NUM> located on the periphery and driving pads connected to the driving chip <NUM> may be vulnerable to static electricity introduced directly from the outside. In addition, since the driving chip <NUM> and the driving pads connected to the driving chip <NUM> are disposed adjacent to a surrounding set structure, they may be vulnerable to static electricity transferred from the surrounding set structure into which static electricity has been initially introduced. The static electricity introduced directly from the outside and the static electricity introduced indirectly may cause a failure of the driving chip <NUM> and the driving pads, if no other electrostatic discharge path is provided, and the failure may cause a screen failure of the display device <NUM>.

<FIG> illustrates a plan view of the non-display area NDA of the display panel <NUM> of the display device <NUM> according to the embodiment, including the driving chip <NUM>, the printed circuit film <NUM>, the cover member <NUM>, and the step compensation member <NUM> when the display device <NUM> is unbent. <FIG> illustrates a cross-sectional view taken along line I-I' of the display device <NUM> of <FIG> when the display device <NUM> is bent. Since <FIG> is a cross-sectional view of the display device <NUM> of <FIG> when the display device <NUM> is bent, the external device is disposed under the display panel <NUM>, and the cover member <NUM> is disposed under the external device in the drawing.

Referring to <FIG> and <FIG>, the cover member <NUM> may completely cover the driving chip <NUM> and partially cover the printed circuit film <NUM>. The cover member <NUM> may include a first insulating layer <NUM> disposed on the external device, a first conductive layer <NUM> disposed on the first insulating layer <NUM>, and a second insulating layer <NUM> disposed on the first conductive layer <NUM>. The first insulating layer <NUM> may include electrostatic transfer openings OP1. This is described later in greater detail.

A planar size of the first insulating layer <NUM> may be substantially equal to a planar size of the first conductive layer <NUM>. The planar size of the first conductive layer <NUM> may be greater than a planar size of the second insulating layer <NUM>. In other words, the planar size of the second insulating layer <NUM> may be smaller than the planar size of the first conductive layer <NUM>.

The cover member <NUM> may have a substantially rectangular planar shape. The cover member <NUM> may include a first end extending along the first direction DR1 and adjacent to the bending area BA in plan view and second and third ends connected to the first end and extending along the second direction DR2. The second end of the cover member <NUM> may face and be adjacent to a profile of the protruding part of the display panel <NUM> on the second side of the first direction DR1, and the third end of the cover member <NUM> may face and be adjacent to a profile of the protruding part of the display panel <NUM> on the first side of the first direction DR1. The first end of the cover member <NUM> may include a straight line extending along the first direction DR1. The first end of the cover member <NUM> may be composed of one straight line extending along the first direction DR1. In some embodiments, the first end may be composed of a plurality of straight lines extending in different directions. Each of the second and third ends of the cover member <NUM> may include a straight line extending along the second direction DR2. Each of the second and third ends of the cover member <NUM> may be composed of one straight line extending along the second direction DR2. In some embodiments, each of the second and third ends may be composed of a plurality of straight lines extending in different directions.

Each of the first insulating layer <NUM>, the first conductive layer <NUM>, and the second insulating layer <NUM> may include ends corresponding to the first through third ends of the cover member <NUM>.

For example, the first insulating layer <NUM>, the first conductive layer <NUM> and the second insulating layer <NUM> may respectively include first ends 71a, 75a and 77a corresponding to the first end of the cover member <NUM>, second ends 71b, 75b and 77b corresponding to the second end of the cover member <NUM>, and third ends 71c, 75c and 77c corresponding to the third end of the cover member <NUM>. The ends of each of the first insulating layer <NUM>, the first conductive layer <NUM> and the second insulating layer <NUM> may be substantially the same as the corresponding ends of the cover member <NUM> in extending direction and position.

The second ends 71b and 75b of the first insulating layer <NUM> and the first conductive layer <NUM> may be aligned with the second end 77b of the second insulating layer <NUM>, and the third ends 71c and 75c of the first insulating layer <NUM> and the first conductive layer <NUM> may be aligned with the third end 77c of the second insulating layer <NUM>.

On the other hand, the first ends 71a and 75a of the first insulating layer <NUM> and the first conductive layer <NUM> may not be aligned with the first end 77a of the second insulating layer <NUM> and may be asymmetrical to the first end 77a of the second insulating layer <NUM> in the thickness direction. For example, the first ends 71a and 75a of the first insulating layer <NUM> and the first conductive layer <NUM> may be located closer to the bending area BA than the first end 77a of the second insulating layer <NUM>. As described above, the planar size of the second insulating layer <NUM> may be smaller than the planar size of the first conductive layer <NUM>. This may be because the first end 77a of the second insulating layer <NUM> is located farther from the bending area BA than the first ends 71a and 75a of the first insulating layer <NUM> and the first conductive layer <NUM>.

Since the planar size of the second insulating layer <NUM> is smaller than the planar size of the first conductive layer <NUM> and the first end 77a of the second insulating layer <NUM> is located farther from the bending area BA than the first ends 71a and 75a of the first insulating layer <NUM> and the first conductive layer <NUM>, each of the first insulating layer <NUM> and the first conductive layer <NUM> may be located closer to the display area DA or the bending area BA than the first end 77a of the second insulating layer <NUM>. In other words, the second insulating layer <NUM> may be located farther from the display area DA or the bending area BA than the first ends 71a and 75a of the first insulating layer <NUM> and the first conductive layer <NUM>. The first end 77a of the second insulating layer <NUM> may be located closer to the external device than the first ends 71a and 75a of the first insulating layer <NUM> and the first conductive layer <NUM>.

An electrostatic induction opening OP2 of the second insulating layer <NUM> may be located in a part of each of the first insulating layer <NUM> and the first conductive layer <NUM> which protrudes further toward the display area DA or the bending area BA than the first end 77a of the second insulating layer <NUM>. In plan view, the electrostatic induction opening OP2 may be surrounded by the first end 75a, the second end 75b and the third end 75c of the first conductive layer <NUM> and the first end 77a of the second insulating layer <NUM>. The electrostatic induction opening OP2 completely penetrates <NUM> the second insulating layer <NUM> in the thickness direction from a surface of the second insulating layer <NUM>.

In the electrostatic induction opening OP2, a part of the first conductive layer <NUM> which protrudes further toward the display area DA or the bending area BA than the first end 77a of the second insulating layer <NUM> may be completely exposed to the outside.

The electrostatic transfer openings OP1 may completely penetrate the first insulating layer <NUM> from a surface of the first insulating layer <NUM>. The electrostatic transfer openings OP1 may overlap the cover member <NUM> and the printed circuit film <NUM> in the thickness direction. The electrostatic transfer openings OP1 may overlap the display panel <NUM> in the thickness direction, but embodiments are not limited to this case. Although three electrostatic transfer openings OP1 are illustrated in <FIG>, the number of the electrostatic transfer openings OP1 may also be one, two, or four or more.

The step compensation member <NUM> may be disposed between the bending area BA and the driving chip <NUM> in plan view. The step compensation member <NUM> may compensate for a step or a space created between the display panel <NUM> and the cover member <NUM> due to the external device. The step compensation member <NUM> may prevent warpage of the cover member <NUM> by compensating for the step or the space between the display panel <NUM> and the cover member <NUM>. Therefore, the step compensation member <NUM> may include a material having a certain degree of strength or rigidity.

The step compensation member <NUM> may include a first step compensation member <NUM> disposed on the display panel <NUM> and a second step compensation member <NUM> disposed on the first step compensation member <NUM>. The first step compensation member <NUM> may be disposed between the second step compensation member <NUM> and the display panel <NUM>. The first step compensation member <NUM> and the second step compensation member <NUM> may overlap each other in the thickness direction. The second step compensation member <NUM> may further include a part protruding further toward the bending are BA than the first step compensation member <NUM>. In other words, the first step compensation member <NUM> may further include a part recessed further toward the external device than the second step compensation member <NUM>. The recessed part of the first step compensation member <NUM> may be designed to avoid interference between a bending protection layer material flowing around the step compensation member <NUM> and the step compensation member <NUM> because the bending protection layer material may flow around the step compensation member <NUM> when the bending protection layer BPL is coated in the bending area BA.

The first insulating layer <NUM> may protect the driving chip <NUM> by completely covering the driving chip <NUM>.

The first insulating layer <NUM> may include a first base <NUM> and a first bonding layer <NUM>, the first conductive layer <NUM> may include a second base <NUM> and a second bonding layer <NUM>, and the second insulating layer <NUM> may include a third base <NUM> and a third bonding layer <NUM>.

Each of the bases <NUM> and <NUM> may include at least one of polyethylene terephthalate (PET), polyimide (PI), polycarbonate (PC), polyethylene (PE), polypropylene (PP), polysulfone (PSF), polymethyl methacrylate (PMMA), triacetyl cellulose (TAC), and cyclo olefin polymer (COP).

Each of the bonding layers <NUM>, <NUM> and <NUM> may include an adhesive layer, a sticky layer, or a resin layer. For example, each of the bonding layers <NUM>, <NUM> and <NUM> may contain a polymer material classified as silicone-based, urethane-based, silicone-urethane (SU) hybrid polymer, acrylic-based, isocyanate-based, polyvinyl alcohol-based, gelatin-based, vinyl-based, latex-based, polyester-based, or aqueous polyester-based. In an embodiment, the second bonding layer <NUM> may further include a conductive material.

The second base <NUM> may include a conductive layer. The conductive layer may include a metal or a metal oxide.

In each of the electrostatic transfer openings OP1, the first insulating layer <NUM> may be completely penetrated in the thickness direction. A second conductive layer <NUM> may be further disposed in each of the electrostatic transfer openings OP1. The cover member <NUM> may further include the second conductive layer <NUM>. The second conductive layer <NUM> may include a fourth base <NUM> and a fourth bonding layer <NUM>. The fourth base <NUM> may include a conductive layer. The conductive layer may include a metal or a metal oxide. The fourth bonding layer <NUM> may include an adhesive layer, a sticky layer, or a resin layer. In an embodiment, the fourth bonding layer <NUM> may further include a conductive material.

The first base <NUM> may be bonded to the driving chip <NUM>, the printed circuit film <NUM> and the step compensation member <NUM> through the first bonding layer <NUM>, the second base <NUM> may be bonded to the first base <NUM> through the second bonding layer <NUM>, the third base <NUM> may be bonded to the second base <NUM> through the third bonding layer <NUM>, the fourth base <NUM> may be bonded to the second base <NUM> through the second bonding layer <NUM>, and the fourth base <NUM> may be bonded to the printed circuit film <NUM> through the fourth bonding layer <NUM>.

The first insulating layer <NUM>, the first conductive layer <NUM> and the second insulating layer <NUM> may respectively include side surfaces 71S1, 75S1 and 77S1 of the first ends 71a, 75a and 77a adjacent to the bending area BA. The side surface 71S1 of the first insulating layer <NUM> and the side surface 75S1 of the first conductive layer <NUM> may be aligned in the thickness direction. The side surface 77S1 of the second insulating layer <NUM> may be located farther from the bending area BA than the side surface 71S1 of the first insulating layer <NUM> and the side surface 75S1 of the first conductive layer <NUM>. In other words, the side surface 71S1 of the first insulating layer <NUM> and the side surface 75S1 of the first conductive layer <NUM> may be located closer to the bending area BA than the side surface 77S1 of the second insulating layer <NUM>, and the side surface 77S1 of the second insulating layer <NUM> may be located closer to the external device than the side surface 71S1 of the first insulating layer <NUM> and the side surface 75S1 of the first conductive layer <NUM>.

A gap W1 between the side surface 77S1 of the second insulating layer <NUM> and the side surface 75S1 of the first conductive layer <NUM> may be equal to a gap between the first end 77a of the second insulating layer <NUM> and the first end 75a of the first conductive layer <NUM>. The gap W1 between the side surface 77S1 of the second insulating layer <NUM> and the side surface 75S1 of the first conductive layer <NUM> may be equal to a width of the electrostatic induction opening OP2 in the second direction DR2.

The gap W1 between the side surface 77S1 of the second insulating layer <NUM> and the side surface 75S1 of the first conductive layer <NUM> may be, for example, <NUM> to <NUM>. In other words, a width in the second direction DR2 of a part of the first conductive layer <NUM> exposed by the second insulating layer <NUM> may be <NUM> to <NUM>.

<FIG> illustrates induction of external static electricity through the electrostatic induction opening OP2.

Referring to <FIG>, a gap between the display panel <NUM> of the display device <NUM> and the external device and the surrounding set structure disposed on the display panel <NUM> is narrow. In addition, when the display device <NUM> is bent, the driving chip <NUM> is positioned outside the printed circuit film <NUM> (for example, in the direction opposite to the direction toward the display area DA) and thus located on the periphery of the display device <NUM> as described above. The driving chip <NUM> located on the periphery and the driving pads connected to the driving chip <NUM> may be vulnerable to static electricity introduced directly from the outside. In addition, since the driving chip <NUM> and the driving pads connected to the driving chip <NUM> are disposed adjacent to the surrounding set structure, they may be vulnerable to static electricity transferred from the surrounding set structure into which static electricity has been initially introduced. The static electricity introduced directly from the outside and the static electricity introduced indirectly may cause a failure of in the driving chip <NUM> and the driving pads, and the failure may cause a screen failure of the display device <NUM>.

When external static electricity is present, a static electricity portion ESD may be introduced through the exposed side surface 75S1 of the first conductive layer <NUM>, and this introduced static electricity portion ESD may be induced or diverted through the first conductive layer <NUM> and the electrostatic transfer openings OP1 to the printed circuit film <NUM>, to which the ground voltage has been applied through the second conductive layer <NUM>, to safely discharge this static electricity portion ESD. However, when the first conductive layer <NUM> has a relatively small thickness of about <NUM> or less, the amount of the divertible static electricity portion ESD introduced through the exposed side surface 75S1 of the first conductive layer <NUM> may be insignificant, or almost none. Without a path to divert a greater portion of the external static electricity introduced directly from the outside and the static electricity introduced indirectly, without being intercepted by the conductive layer <NUM> and diverted through the transfer openings OP1, such static electricity might be undesirably applied to the driving chip <NUM> located on the periphery and the driving pads connected to the driving chip <NUM>.

Thus, the cover member <NUM> of the display device <NUM> according to this embodiment includes the second electrostatic induction opening OP2, which is considerably wider than the exposed side surface 75S1 of the first conductive layer <NUM>, and this electrostatic induction opening OP2 induces a greater portion or substantially all of the static electricity introduced directly from the outside and the static electricity introduced indirectly through the conductive layer <NUM> to be diverted through the first electrostatic transfer openings OP1 to the grounded printed circuit film <NUM>. Therefore, it is possible to prevent static electricity from being applied to the driving chip <NUM> located on the periphery and the driving pads connected to the driving chip <NUM>, thereby preventing a screen failure of the display device <NUM>. Although three electrostatic transfer openings OP1 are provided in this embodiment, it shall be understood that alternate embodiments may include any greater or lesser number of electrostatic transfer openings OP1, such as one or twenty, without limitation.

<FIG> illustrates a plan view of a non-display area NDA of a display panel <NUM> according to an embodiment, a driving chip <NUM>, a printed circuit film <NUM>, a cover member, and a step compensation member <NUM> when the display panel <NUM> is unbent. <FIG> illustrates a cross-sectional view taken along line II-II' of <FIG> when the display panel <NUM> is bent. <FIG> illustrates a cross-sectional view taken along line III-III' of <FIG> when the display panel <NUM> is bent.

Referring to <FIG>, a display device <NUM> according to the current embodiment is different from the display device <NUM> of <FIG> and <FIG> in that an electrostatic induction opening OP2_1 is located between a second end 75b of a first conductive layer <NUM> and a second end 77b_1 of a second insulating layer 77_1.

More specifically, in the display device <NUM> according to the current embodiment, the electrostatic induction opening OP2_1 may be located between the second end 75b of the first conductive layer <NUM> and the second end 77b_1 of the second insulating layer 77_1. Further, an electrostatic induction opening OP2_2 may be disposed between a third end 75c of the first conductive layer <NUM> and a third end 77c_1 of the second insulating layer 77_1.

First ends 71a and 75a of a first insulating layer <NUM> and the first conductive layer <NUM> may be aligned with a first end 77a_1 of the second insulating layer 77_1. Second ends 71b and 75b of the first insulating layer <NUM> and the first conductive layer <NUM> may not be aligned with the second end 77b_1 of the second insulating layer 77_1 and may be asymmetrical to the second end 77b_1 of the second insulating layer 77_1 in the thickness direction.

For example, the second ends 71b and 75b of the first insulating layer <NUM> and the first conductive layer <NUM> may be located farther from the driving chip <NUM> than the second end 77b_1 of the second insulating layer 77_1. Likewise, third ends 71c and 75c of the first insulating layer <NUM> and the first conductive layer <NUM> may be located farther from the driving chip <NUM> than the third end 77c_1 of the second insulating layer 77_1. As described above, a planar size of the second insulating layer 77_1 may be smaller than a planar size of the first conductive layer <NUM>. This may be because the second and third ends 77b_1 and 77c_1 of the second insulating layer 77_1 are located closer to the driving chip <NUM> than the second and third ends 71b, 75b, 71c and 75c of the first insulating layer <NUM> and the first conductive layer <NUM>.

Each of the first insulating layer <NUM> and the first conductive layer <NUM> may protrude from the second and third ends 77b_1 and 77c_1 of the second insulating layer <NUM> in directions away from the driving chip <NUM>. The electrostatic induction openings OP2_1 and OP2_2 of the second insulating layer 77_1 may be located in each of the protruding parts. In plan view, the electrostatic induction opening OP2_1 may be located between the second end 75b of the first conductive layer <NUM> and the second end 77b_1 of the second insulating layer 77_1 and the electrostatic induction opening OP2_2 may be located between the third end 75c of the first conductive layer <NUM> and the third end 77c_1 of the second insulating layer 77_1.

In the electrostatic induction opening OP2_1, a part of the first conductive layer <NUM> which protrudes from the second end 77b_1 of the second insulating layer 77_1 in the direction away from the driving chip <NUM> may be completely exposed to the outside. Similarly, in the electrostatic induction opening OP2_2, a part of the first conductive layer <NUM> which protrudes from the third end 77c_1 of the second insulating layer 77_1 in the direction away from the driving chip <NUM> may be completely exposed to the outside.

Each of the first insulating layer <NUM>, the first conductive layer <NUM> and the second insulating layer 77_1 may include side surfaces corresponding to its ends. A side surface 75S1 of the first end 71a of the first conductive layer <NUM> may be aligned with a side surface 77_1S1 of the first end 77a_1 of the second insulating layer 77_1. Side surfaces 77_1S2 and 77_1S3 of the second end 77b_1 and the third end 77c_1 of the second insulating layer 77_1 may be located closer to the driving chip <NUM> than side surfaces 75S2 and 75S3 of the second end 75b and the third end 75c of the first conductive layer <NUM>, respectively.

In the current embodiment, the electrostatic induction openings OP2_1 and OP2_2, which are considerably wider than the exposed side surface 75S1 of the first conductive layer <NUM>, may also be included to induce static electricity introduced directly from the outside and static electricity introduced indirectly. Therefore, it is possible to prevent static electricity from being applied to the driving chip <NUM> located on the periphery and driving pads connected to the driving chip <NUM>, thereby preventing a screen failure of the display device <NUM>. In alternate embodiments, electrostatic induction openings OP2_1 and/or OP2_2 may be included without limitation.

<FIG> illustrates a plan view of a non-display area NDA of a display panel <NUM> according to an embodiment, a driving chip <NUM>, a printed circuit film <NUM>, a cover member, and a step compensation member <NUM> when the display panel <NUM> is unbent.

Referring to <FIG>, a display device <NUM> according to the current embodiment is different from the display device <NUM> including the electrostatic induction opening OP2 described above with reference to <FIG> and <FIG> in that it further includes the electrostatic induction openings OP2_1 and OP2_2 described above with reference to <FIG>.

More specifically, a second insulating layer 77_2 of the display device <NUM> according to the current embodiment may include the electrostatic induction openings OP2_1 and OP2_2 described above with reference to <FIG>, and the electrostatic induction opening OP2 described above with reference to <FIG> and <FIG>.

The electrostatic induction opening OP2 and the electrostatic induction openings OP2_1 and OP2_2 of the display device <NUM> according to the current embodiment may surround the driving chip <NUM> from the first side of the second direction DR2 and the first and second sides of the first direction DR1.

In the current embodiment, the electrostatic induction openings OP2, OP2_1 and OP2_2, which are considerably wider than an exposed side surface 75S1 of a first conductive layer <NUM>, may also be included to induce static electricity introduced directly from the outside and static electricity introduced indirectly towards ground. Therefore, it is possible to prevent static electricity from being applied to the driving chip <NUM> located on the periphery and driving pads connected to the driving chip <NUM>, thereby preventing a screen failure of the display device <NUM>.

<FIG> illustrates a cross-sectional view of a display device <NUM> according to an embodiment.

Referring to <FIG>, the display device <NUM> according to the current embodiment is different from the display device <NUM> according to the embodiment of <FIG> in that a cover member further includes a conductive outer layer <NUM> disposed on a second insulating layer 77_3.

More specifically, in the display device <NUM> according to the current embodiment, the cover member may further include the conductive outer layer <NUM> disposed on the second insulating layer 77_3.

In the cover member according to the current embodiment, side surfaces 71S1 and 75S1 of a first insulating layer <NUM> and a first conductive layer <NUM> may be aligned with a side surface 77_3S1 of the second insulating layer 77_3.

The second insulating layer 77_3 may be disposed between the conductive outer layer <NUM> and the first conductive layer <NUM>. The conductive outer layer <NUM> may be disposed on an edge part (adjacent to a bending area BA) of the second insulating layer 77_3. The conductive outer layer <NUM> may overlap the edge part (adjacent to the bending area BA) of the second insulating layer 77_3 in the thickness direction. The side surface 71S1 of the first insulating layer <NUM>, the side surface 75S1 of the first conductive layer <NUM>, and the side surface 77_3S1 of the second insulating layer 77_3 may be exposed to the outside.

The conductive outer layer <NUM> may include at least one of the materials mentioned as example materials of a second base <NUM> of the first conductive layer <NUM>.

In the current embodiment, since the display device <NUM> further includes the conductive outer layer <NUM> overlapping, in the thickness direction, the edge part (adjacent to the bending area BA) of the second insulating layer 77_3 located on an outermost side of the cover member, static electricity introduced directly from the outside and static electricity introduced indirectly may be induced to the conductive outer layer <NUM> and conducted to the first conductive layer <NUM> because the second insulating layer 77_3 is thinner than the first conductive layer <NUM>. Therefore, it is possible to prevent static electricity from being applied to a driving chip <NUM> located on the periphery and driving pads connected to the driving chip <NUM>, thereby preventing a screen failure of the display device <NUM>. In an alternate embodiment where the second insulating layer 77_3 need not be thinner than the first conductive layer <NUM>, the conductive outer layer <NUM> may be disposed on an electrostatic induction opening that extends through the second insulating layer 77_3 to the first conductive layer <NUM>.

Referring to <FIG>, the display device <NUM> according to the current embodiment is different from the display device <NUM> of <FIG> in that a conductive outer layer 86_1 is further disposed on a side surface 77_3S1 of a second insulating layer 77_3 and a side surface 75S1 of a first conductive layer <NUM>.

More specifically, in the display device <NUM> according to the current embodiment, the conductive outer layer 86_1 may be further disposed on the side surface 77_3S1 of the second insulating layer 77_3 and the side surface 75S1 of the first conductive layer <NUM>.

Since the conductive outer layer 86_1 is further disposed on the side surface 77_3S1 of the second insulating layer 77_3 and the side surface 75S1 of the first conductive layer <NUM>, it may be electrically connected to the first conductive layer <NUM>.

In the current embodiment, since the display device <NUM> further includes the conductive outer layer 86_1 overlapping, in the thickness direction, an edge part (adjacent to a bending area BA) of the second insulating layer 77_3 located on an outermost side of the cover member, static electricity introduced directly from the outside and static electricity introduced indirectly may be induced to the conductive outer layer 86_1 and conducted directly to the first conductive layer <NUM>. Therefore, it is possible to prevent static electricity from being applied to a driving chip <NUM> located on the periphery and driving pads connected to the driving chip <NUM>, thereby preventing a screen failure of the display device <NUM>. In an alternate embodiment, the conductive outer layer 86_1 may be disposed on an electrostatic induction opening OP3 that extends through the second insulating layer 77_3 to the first conductive layer <NUM>.

In a display device according to the present disclosure, display screen failures due to external stress, for example, static electricity can be improved.

However, the effects of the embodiments are not restricted to the one set forth herein. The above and other effects of the embodiments will become more apparent to one of daily skill in the art to which the embodiments pertain by referencing the claims.

Claim 1:
A flexible display panel (<NUM>) comprising:
a display area (DA);
a non-display area (NDA) located around the display area;
an external device (<NUM>, <NUM>) which is disposed on the non-display area of the display panel, wherein the external device comprises a driving chip (<NUM>) and a printed circuit film (<NUM>), wherein the printed circuit chip is grounded;
a cover (<NUM>) disposed on the external device (<NUM>, <NUM>) and comprising a first insulating layer (<NUM>) disposed on the external device (<NUM>, <NUM>), a conductive layer (<NUM>) disposed on the first insulating layer (<NUM>), and a second insulating layer (<NUM>) disposed on the conductive layer,
wherein the first insulating layer (<NUM>) comprises at least one electrostatic transfer opening (OP1) extending between the conductive layer (<NUM>) and the external device (<NUM>, <NUM>);
and wherein the second insulating layer (<NUM>) comprises an electrostatic induction opening (OP2) completely penetrating the second insulating layer (<NUM>) in a thickness direction from a surface of the second insulating layer and defined
where a planar size of the conductive layer (<NUM>) is greater than a planar size of the second insulating layer (<NUM>).