Patent Description:
A flat panel display device (e.g., an organic light emitting display OLED device) may have advantages in terms of being light in weight and thin in thickness. The development of flexible display devices may take advantage of these characteristics of flat panel display devices. A flexible display device may include a curved display device, a bent display device, a foldable display device, a rollable display device, a stretchable display device, and the like. A flexible display device may include a display module and a support member disposed under the display module. In case that the support member is deformed, the display module supported by the support member may be deformed. Accordingly, wrinkles may occur on an upper surface of the display module, and the flexible characteristic of the display module may be reduced.

It is to be understood that this background of the technology section is, in part, intended to provide useful background for understanding the technology. However, this background of the technology section may also include ideas, concepts, or recognitions that were not part of what was known or appreciated by those skilled in the pertinent art prior to a corresponding effective filing date of the subject matter disclosed herein.

<CIT> and <CIT> disclose a display device including a lattice portion overlapping a folding portion.

Embodiments may provide a display device having flexible characteristics.

According to an embodiment, a flexible display device is provided as defined in claim <NUM>.

In an embodiment, the support part may further include a first support portion overlapping the first flat portion, and a second support portion overlapping the second flat portion, and the shape holding portion, the first support portion, and the second support portion may be integral with each other.

In an embodiment, the shape holding portion may be disposed between the first support portion and the second support portion.

In an embodiment, the shape holding portion may be adjacent to an outermost area of the support part.

In an embodiment, the display device may further include a deco pattern disposed on the display part and overlapping the outermost area of the support part.

In an embodiment, the deco pattern may cover a side surface of the shape holding portion.

In an embodiment, the shape holding portion may include a first portion adjacent to the lattice portion in the second direction, and a second portion adjacent to the lattice portion in a third direction opposing the second direction.

In an embodiment, a width of the boundary hole in the first direction may be equal to a width of the lattice portion in the first direction.

In an embodiment, a size of the boundary hole may be larger than a size of each of the holes.

In an embodiment, the holes may penetrate the support part in a thickness direction of the support part.

In an embodiment, the folding portion may include a plurality of folding portions disposed between the first flat portion and the second flat portion, and the lattice portion may include a plurality of lattice portions and the shape holding portion may include a plurality of shape holding portions. The pluratily of holes may be disposed in each of the plurality of lattice portions, the plurality of shape holding portions may be adjacent to the plurality of lattice portions in the second direction intersecting the first direction, and the plurality of lattice portions and the plurality of shape holding portions may overlap the plurality of folding portions.

In an embodiment, the folding portions may include a first folding portion, a second folding portion disposed between the first flat portion and the first folding portion, and a third folding portion disposed between the first folding portion and the second flat portion. The lattice portions may include a first gird portion overlapping the first folding portion, a second lattice portion overlapping the second folding portion, and a third lattice portion overlapping the third folding portion. The shape holding portions may include a first shape holding portion adjacent to the second lattice portion, and a second shape holding portion adjacent to the third lattice portion.

In an embodiment, a curvature of the second folding portion and a curvature of the third folding portion may be smaller than a curvature of the first folding portion.

In an embodiment, the support part may have a structure symmetrical with respect to the first lattice portion.

In an embodiment, a first hole and a boundary hole connected to the first hole may be disposed in the second lattice portion.

In an embodiment, a second hole not connected to the boundary hole may be further disposed in the second lattice portion.

In an embodiment, the shape holding portions may be adjacent to an outermost area of the support part.

In an embodiment, the display device may further include a deco pattern disposed on the display part and overlapping the outermost area.

A display device according to the embodiments may include a display part (e.g., module) including at least one folding portion and a support part (e.g., member) disposed under the display module. The support member may include a lattice portion in which holes may be formed and a shape holding portion adjacent to the lattice portion. The lattice portion and the shape holding portion may overlap the folding portion. The shape holding portion may maintain a shape of the support member. For example, the shape holding portion may prevent the lattice portion having relatively weak rigidity by the holes from being deformed. Accordingly, wrinkles due to folding may not be formed on the upper surfaces of the display device, and the display device may easily perform folding and unfolding.

Illustrative, non-limiting embodiments will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings in which:.

Hereinafter, display devices in accordance with embodiments will be explained in detail with reference to the accompanying drawings. This disclosure may, however, be embodied in different forms and should not be construed as 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 scope of the disclosure to those skilled in the art.

As used herein, the singular forms, "a," "an," and "the" are intended to include the plural forms as well (and vice versa), unless the context clearly indicates otherwise.

In the specification and the claims, the term "and/or" is intended to include any combination of the terms "and" and "or" for the purpose of its meaning and interpretation. For example, "A and/or B" may be understood to mean "A, B, or A and B. " The terms "and" and "or" may be used in the conjunctive or disjunctive sense and may be understood to be equivalent to "and/or.

In the specification and the claims, the phrase "at least one of" is intended to include the meaning of "at least one selected from the group of" for the purpose of its meaning and interpretation. For example, "at least one of A and B" may be understood to mean "A, B, or A and B.

The terms "comprises," "comprising" "includes" and/or "including,", "has," "have," and/or "having," and variations thereof when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

The terms "overlap" or "overlapped" mean that a first object may be above or below or to a side of a second object, and vice versa. Additionally, the term "overlap" may include layer, stack, face or facing, extending over, covering, or partly covering or any other suitable term as would be appreciated and understood by those of ordinary skill in the art.

The terms "face" and "facing" mean that a first element may directly or indirectly oppose a second element. In a case in which a third element intervenes between the first and second element, the first and second element may be understood as being indirectly opposed to one another, although still facing each other.

It will be understood that the terms "connected to" or "coupled to" may include a physical or electrical connection or coupling.

"About", "approximately", and "substantially" as used herein are inclusive of the stated value and mean within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system).

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosure pertains.

<FIG> is a schematic plan view illustrating an unfolded state of a display device according to an embodiment. <FIG> is a schematic perspective view illustrating a folded state of the display device of <FIG>.

Referring to <FIG> and <FIG>, a display device <NUM> according to an embodiment may include a display part (e.g., module) DM, a deco pattern DP, and a set cover SC.

The display module DM may include a display area DA and a non-display area NDA. An image may be displayed in the display area DA, and the non-display area NDA may be disposed to surround the display area DA. The non-display area NDA may constitute a bezel of the display device <NUM>.

The display module DM may repeatedly perform folding and unfolding. In an embodiment, the display module DM may include a flexible substrate (e.g., a plastic substrate). In case that the display module DM is folded according to an external force applied by a user, a planar size of the display device <NUM> may be reduced. In case that the display module DM is unfolded according to an external force applied by a user, the display area DA may be exposed.

The deco pattern DP may be disposed between the display module DM and a window (e.g., a window WIN in <FIG>), and may overlap the non-display area NDA. In an embodiment, the deco pattern DP may have a color. For example, the deco pattern DP may have black, white, or the like. The deco pattern DP may prevent the display module DM from being deformed, and may prevent the deformed display module DM from being visually recognized by the user.

The set cover SC may include a first set cover SC1, a second set cover SC2, and a hinge cover HC. The first set cover SC1 and the second set cover SC2 may be connected to each other by the hinge cover HC. Based on the hinge cover HC, the display device <NUM> may be folded and unfolded. The first set cover SC1 may support a first flat portion (e.g., a first flat portion EP1 in <FIG>) of the display module DM. The second set cover SC2 may support a second flat portion (e.g., a second flat portion EP2 in <FIG>) of the display module DM.

<FIG> is a schematic cross-sectional view illustrating a folded state of the display device of <FIG>. <FIG> is a schematic plan view illustrating a support part (e.g., member) included in the display device of <FIG>.

Referring to <FIG>, <FIG>, and <FIG>, the display device <NUM> may include the display module DM, the support member SM, and the set cover SC. The display module DM includes a first flat portion EP1, a second flat portion EP2, and a folding portion FP disposed between the first flat portion EP1 and the second flat portion EP2. The support member SM may include a first support portion SP1, a second support portion SP2,. Further, the support member SM inlcudes a lattice portion LP, and a shape holding portion SHP.

In case that the display device <NUM> is folded, the display module DM may be folded so that portions of a display surface S1 face each other. For example, in case that an external force is applied by a user to the display device <NUM> in an unfolded state, the first set cover SC1 may rotate in a clockwise direction, and the second set cover SC2 may rotate in a counterclockwise direction. Accordingly, the display surface S1 of the first flat portion EP1 and the display surface S1 of the second flat portion EP2 may face each other.

The support member SM isdisposed under the display module DM. In an embodiment, the support member SM may be formed of metal and may support the display module DM. For example, the support member SM may include at least one of invar which may be an alloy of nickel ("Ni") and iron ("Fe"), stainless steel ("SUS"), titanium ("Ti"), and copper ("Cu"). In another embodiment, the support member SM may be formed of a non-metal, plastic, glass fiber reinforced plastic and/or glass. For example, the plastic may include polyimide, polyethylene, polyethylene terephthalate, and the like, and is not particularly limited.

In an embodiment, the first support portion SP1 overlaps the first flat portion EP1. Accordingly, the first support portion SP1 may support the first flat portion EP1. The second support portion SP2 overlaps the second flat portion EP2. Accordingly, the second support portion SP2 may support the second flat portion EP2.

In an embodiment, the lattice portion LP overlaps the folding portion FP. Accordingly, the lattice portion LP may support the folding portion FP. Holes HL are formed in the lattice portion LP. The holes HL may penetrate the support member SM in a thickness direction of the support member SM. As the holes HL may penetrate the support member SM, the support member SM may be smoothly folded. Accordingly, the display module DM may be smoothly folded.

In an embodiment, the shape holding portion SHP may include a first portion P1 and a second portion P2. The first portion P1 may be adjacent to the lattice portion LP in a second direction D2 crossing the first direction D1. The second portion P2 may be adjacent to the lattice portion LP in a fourth direction D4 opposite to the second direction D2. The shape holding portion SHP may be integrally formed with the first support portion SP1 and the second support portion SP2, and may be disposed between the first support portion SP1 and the second support portion SP2.

The shape holding portion SHP may be disposed to be adjacent to an outermost area of the support member SM, and may overlap the folding portion FP. In other words, the first portion P1 may be disposed to be adjacent to an upper end of the support member SM, and may overlap the folding portion FP. The second portion P2 may be disposed to be adjacent to a lower end of the support member SM, and may overlap the folding portion FP.

The shape holding portion SHP maintains a shape of the support member SM. In detail, the shape holding portion SHP may prevent the lattice portion LP having relatively weak rigidity from being deformed. For example, due to the holes HL formed in the lattice portion LP, the lattice portion LP may be expanded in the first direction D1 and a third direction D3 opposite to the first direction D1. The holes HL may be deformed. However, as the shape holding portion SHP may be integrally formed with the first and second support portions SP1 and SP2, the shape holding portion SHP may prevent the lattice portion LP from being expanded or the holes HL from being deformed.

In an embodiment, a first boundary hole BHL1 and a second boundary hole BHL2 are further formed in the lattice portion LP. The first boundary hole BHL1 may connect the holes HL adjacent to the first portion P1 to each other. The second boundary hole BHL2 may connect the holes HL adjacent to the second portion P2 to each other.

The first boundary hole BHL1 and the second boundary hole BHL2 may define a boundary between the holes HL and the shape holding portion SHP. In other words, the first boundary hole BHL1 and the second boundary hole BHL2 may separate the shape holding portion SHP from the holes HL. Accordingly, the shape holding portion SHP may effectively maintain the shape of the support member SM.

In an embodiment, a width of the first boundary hole BHL1 in the first direction D1 and a width of the second boundary hole BHL2 in the first direction D1 may be substantially equal to a width of the lattice portion LP in the first direction D1. A size of the first boundary hole BHL1 (e.g., a plane area of the first boundary hole BHL1) and a size of the second boundary hole BHL2 may be larger than a size of each of the holes HL.

<FIG> is a schematic cross-sectional view taken along line I-I' of <FIG>. <FIG> is a schematic cross-sectional view taken along line II-II' of <FIG>. <FIG> is a schematic cross-sectional view taken along line III-III' of <FIG>.

Referring to <FIG>, the display device <NUM> may include the set cover SC, the support member SM, a cushion member CM, a protective film PFL, the display module DM, the deco pattern DP, and the window WIN.

The first set cover SC1 may overlap the first support portion SP1 and the first flat portion EP1. The first set cover SC1 may support the first support portion SP1 and the first flat portion EP1. The second set cover SC2 may overlap the second support portion SP2 and the second flat portion EP2. The second set cover SC2 may support the second support portion SP2 and the second flat portion EP2.

The support member SM may be disposed on the set cover SC. The shape holding portion SHP may be disposed to be adjacent to the outermost area of the support member SM, and may overlap the folding portion FP.

In an embodiment, the cushion member CM may be disposed on the support member SM. The cushion member CM may buffer an external shock that may be applied to the display module DM, and may protect the display module DM. For example, the cushion member CM may include a material capable of buffering by containing air, such as a cushion and a sponge. In order to facilitate folding and unfolding of the display module DM, the cushion member CM may include a flexible material. For example, the cushion member CM may include an acrylic resin, polyurethane, thermoplastic polyurethane ("TPU"), latex, polyurethane foam, polystyrene foam, or a combination thereof. In another embodiment, the cushion member CM may be disposed under the support member SM.

The protective film PFL may be disposed on the cushion member CM. The protective film PFL may prevent penetration of moisture and oxygen from the outside and may absorb external impact. In order to implement a flexible display device, the display module DM may include a flexible plastic substrate, and the protective film PFL may support the plastic substrate.

For example, the protective film PFL may be a plastic film. For example, the protective film PFL may include polyethersulfone ("PS"), polyacrylate, polyetherimide ("PEI"), polyethylenenaphthalate ("PEN"), polyphenylene sulfide ("PPS"), polyarylate ("PAR"), polycarbonate ("PC"), poly(arylene ethersulfone), polyethylene terephthalate ("PET"), polyimide ("PI"), and the like, or a combination thereof.

The display module DM may be disposed on the protective film PFL. The display module DM will be described with reference to <FIG>.

The window WIN may be disposed on the display module DM. The window WIN may constitute a front surface of the display device <NUM> and may protect the display module DM. The window WIN may include polymethyl methacrylate ("PMMA"), polyethylene terephtalate ("PET"), or the like.

Referring to <FIG>, the support member SM may be disposed on the set cover SC. The lattice portion LP may overlap the folding portion FP, and the first and second support portions SP1 and SP2 may overlap the first and second flat portions EP1 and EP2, respectively. The holes HL may be formed in the lattice portion LP. By the holes HL, the folding portion FP may be smoothly folded.

Referring to <FIG>, in an embodiment, the deco pattern DP may overlap the shape holding portion SHP. For example, the deco pattern DP may overlap the first portion P1 and the second portion P2. In other words, the deco pattern DP may overlap the outermost area. The deco pattern DP may cover a side surface of the shape holding portion SHP. As the deco pattern DP overlaps the shape holding portion SHP and covers the side surface of the shape holding portion SHP, the deco pattern DP may prevent the display module DM from being deformed and may prevent the deformed display module DM from being visually recognized by the user.

<FIG> is a schematic cross-sectional view illustrating a display part (e.g., module) included in the display device of <FIG>.

Referring to <FIG>, the display module DM may include a display panel <NUM>, a sensing layer <NUM>, and a polarizing layer <NUM>. Each of the display panel <NUM>, the sensing layer <NUM>, and the polarizing layer <NUM> may have flexible characteristics.

The display panel <NUM> may include pixels, and may generate an image in which light emitted from each of the pixels may be combined. The light may be emitted toward the display surface S1, and the non-display surface S2 of the display panel <NUM> may be a non-display surface S2 of the display module DM.

The sensing layer <NUM> may be disposed on the display panel <NUM>. The sensing layer <NUM> may sense an external input, such as when an external object contacts or approaches the display device <NUM>. For example, the sensing layer <NUM> may sense the external input in a capacitive method.

The polarizing layer <NUM> may be disposed on the sensing layer <NUM>. The polarizing layer <NUM> may reduce reflection of external light from the display device <NUM>. For example, in case that external light passes through the polarizing layer <NUM> and is reflected from the lower portion (e.g., the display panel <NUM>) of the polarizing layer <NUM> and passes through the polarizing layer <NUM> again, as the external light passes through the polarizing layer <NUM> twice, the phase of the external light may be changed. As the phase of the reflected light may be different from the phase of the incident light passing through the polarizing layer <NUM>, extinction interference may occur between the incident light and the reflected light. Accordingly, reflection of external light may be reduced, and visibility of the display device <NUM> may be improved.

<FIG> is a schematic plan view illustrating a display panel included in the display device of <FIG>. <FIG> is a cross-sectional view illustrating the display panel of <FIG>.

Referring to <FIG> and <FIG>, the display panel <NUM> may include the pixels. Each of the pixels may include a switching thin film transistor T1, a driving thin film transistor T2, a storage capacitor CAP, and a light emitting diode EE. The display panel <NUM> may display an image through the pixels.

As shown in <FIG> and <FIG>, two thin film transistors and one storage capacitor may be disposed in one pixel, but embodiments are not limited thereto. For example, one pixel may include three or more thin film transistors and/or two or more storage capacitors.

The display panel <NUM> may include a substrate <NUM>, a gate line <NUM> disposed on the substrate <NUM>, a data line <NUM> disposed on the gate line <NUM>, and a common power line <NUM>. For example, one pixel may be defined by a boundary between the gate line <NUM>, the data line <NUM>, and the common power line <NUM>. In other embodiments, the pixel may be defined by a black matrix or a pixel defining layer.

The substrate <NUM> may include a flexible material such as plastic. For example, the substrate <NUM> may be formed of polyethersulfone ("PES"), polycarbonate ("PC"), polyimide ("PI"), polyethylene terephthalate ("PET"), polyethylene naphthalate ("PEN"), polyacrylate, fiber reinforced plastic ("FRP"), or the like, or a combination thereof.

The substrate <NUM> may have a thickness of about <NUM> to about <NUM>. When the substrate <NUM> has a thickness less than about <NUM>, it may be difficult for the substrate <NUM> to stably support the light emitting diode EE. In case that the substrate <NUM> has a thickness greater than about <NUM>, the flexible characteristics of the substrate <NUM> may be deteriorated.

The buffer layer <NUM> may be disposed on the substrate <NUM>. The buffer layer <NUM> may prevent penetration of impurities and may serve to planarize a surface. The buffer layer <NUM> may be formed of silicon nitride, silicon oxide, silicon oxynitride, or the like, or a combination thereof. However, the buffer layer <NUM> may be omitted.

A switching semiconductor layer <NUM> and a driving semiconductor layer <NUM> may be disposed on the buffer layer <NUM>. The switching semiconductor layer <NUM> and the driving semiconductor layer <NUM> may be formed of at least one of polycrystalline silicon, amorphous silicon, and an oxide semiconductor (e.g., indium gallium zinc oxide ("IGZO"), indium zinc tin oxide ("IZTO"), etc.). For example, in case that the driving semiconductor layer <NUM> is formed of polycrystalline silicon, the driving semiconductor layer <NUM> may include a channel region that may not be doped with impurities, and a source region and a drain region doped with the impurities. The impurities may vary depending on the type of thin film transistor.

A gate insulating layer <NUM> may be disposed on the switching semiconductor layer <NUM> and the driving semiconductor layer <NUM>. The gate insulating layer <NUM> may be formed of tetraethoxysilane ("TEOS"), silicon nitride, silicon oxide, or the like, or a combination thereof. In an embodiment, the gate insulating layer <NUM> may have a double layer structure in which a silicon nitride layer having a thickness of about <NUM> and a tetraethoxysilane layer having a thickness of about <NUM> may be sequentially stacked on each other.

A gate line including gate electrodes <NUM> and <NUM> may be disposed on the gate insulating layer <NUM>. The gate line may include the gate line <NUM> and a first capacitor plate <NUM>. The gate electrodes <NUM> and <NUM> may be disposed to overlap a portion (e.g., a channel region) of the semiconductor layers <NUM> and <NUM>.

The gate electrodes <NUM> and <NUM> and the first capacitor plate <NUM> may be disposed in the same layer and may be formed of substantially the same metal. For example, the gate electrodes <NUM> and <NUM> and the first capacitor plate <NUM> may be formed of molybdenum ("Mo"), chromium ("Cr"), tungsten ("W"), or the like, or a combination thereof.

An interlayer insulating layer <NUM> covering the gate electrodes <NUM> and <NUM> may be disposed on the gate insulating layer <NUM>. The interlayer insulating layer <NUM> may be formed of tetraethoxysilane, silicon nitride, silicon oxide, or the like.

Data lines including source electrodes <NUM> and <NUM> and drain electrodes <NUM> and <NUM> may be disposed on the interlayer insulating layer <NUM>. The data line may further include a data line <NUM>, the common power line <NUM>, a second power storage plate <NUM>, and the like. The source electrodes <NUM> and <NUM> and the drain electrodes <NUM> and <NUM> may be connected to a source region and a drain region of the semiconductor layers <NUM> and <NUM> through contact holes formed in the gate insulating layer <NUM> and the interlayer insulating layer <NUM>.

The switching thin film transistor T1 may include the switching semiconductor layer <NUM>, the switching gate electrode <NUM>, the switching source electrode <NUM>, and the switching drain electrode <NUM>, and the driving thin film transistor T2 may include the driving semiconductor layer <NUM>, the driving gate electrode <NUM>, the driving source electrode <NUM>, and the driving drain electrode <NUM>. The storage capacitor CAP may include the first storage plate <NUM> and the second storage plate <NUM>.

The switching thin film transistor T1 may be a switching element for selecting a pixel to emit light. The switching gate electrode <NUM> may be connected to the gate line <NUM>. The switching source electrode <NUM> may be connected to the data line <NUM>. The switching drain electrode <NUM> may be spaced apart from the switching source electrode <NUM> and may be connected to the first capacitor plate <NUM>.

The driving thin film transistor T2 may apply a driving power to the pixel electrode <NUM> to emit light of the light emitting diode EE of the selected pixel. The driving gate electrode <NUM> may be connected to the first capacitor plate <NUM>. Each of the driving source electrode <NUM> and the second capacitor plate <NUM> may be connected to the common power line <NUM>. The driving drain electrode <NUM> may be connected to the pixel electrode <NUM> of the light emitting diode EE through a contact hole.

A planarization layer <NUM> covering the data line <NUM>, the common power line <NUM>, the source electrodes <NUM> and <NUM>, the drain electrodes <NUM> and <NUM>, and the second capacitor plate <NUM> may be disposed on the interlayer insulating layer <NUM>.

The planarization layer <NUM> may be planarized by removing a step. The planarization film <NUM> may include an acrylic resin, an epoxy resin, a phenolic resin, a polyamides resin, a polyimide resin, an unsaturated polyester resin, polyphenylenes resin, polyphenylene sulfides resin, benzocyclobutene ("BCB"), and the like, or a combination thereof.

The pixel electrode <NUM> of the light emitting diode EE may be disposed on the planarization layer <NUM>. The pixel electrode <NUM> may be connected to the drain electrode <NUM> through a contact hole formed in the planarization layer <NUM>.

A pixel defining layer <NUM> may be disposed on the planarization layer <NUM> to define a pixel by exposing at least a portion of the pixel electrode <NUM>. The pixel electrode <NUM> may be disposed to correspond to the pixel of the pixel defining layer <NUM>. The pixel defining layer <NUM> may be formed of polyacrylates resin, polyimides resin, or the like, or a combination thereof.

An emission layer <NUM> may be disposed on the pixel electrode <NUM> in the pixel, and a common electrode <NUM> may be disposed on the pixel defining layer <NUM> and the emission layer <NUM>. The emission layer <NUM> may be formed of a low molecular weight organic material or a high molecular weight organic material. At least one of a hole injection layer ("HIL") and a hole transport layer ("HTL") may be further disposed between the pixel electrode <NUM> and the emission layer <NUM>, and at least one of an electron transport layer ("ETL") and an electron injection layer ("EIL") may be further disposed between the emission layer <NUM> and the common electrodes <NUM>.

Each of the pixel electrode <NUM> and the common electrode <NUM> may be at least one of a transmissive electrode, a transflective electrode, and a reflective electrode.

The transmissive electrode may include a transparent conductive oxide ("TCO"). The transparent conductive oxide ("TCO") may include indium tin oxide ("ITO"), indium zinc oxide ("IZO"), zinc oxide ("ZnO"), indium oxide ("In2O3"), or the like, or a combination thereof.

The transflective electrode and the reflective electrode may include metal such as magnesium ("Mg"), silver ("Ag"), gold ("Au"), calcium ("Ca"), lithium ("Li"), chromium ("Cr"), aluminum ("AI"), copper ("Cu"), or alloys thereof.

A thin film encapsulation layer TFE may be disposed on the common electrode <NUM>. The thin film encapsulation layer TFE may include one or more inorganic layers <NUM>, <NUM>, and <NUM> and one or more organic layers <NUM> and <NUM>. The thin film encapsulation layer TFE may have a structure in which the inorganic layers <NUM>, <NUM>, and <NUM> and the organic layers <NUM> and <NUM> may be alternately stacked on each other. The inorganic layer <NUM> may be disposed on a lowermost portion.

The thin film encapsulation layer TFE may include three inorganic layers <NUM>, <NUM>, and <NUM> and two organic layers <NUM> and <NUM> in <FIG>, but embodiments are not limited thereto.

The inorganic layers <NUM>, <NUM>, and <NUM> may be formed of one or more inorganic materials of Al2O3, TiO2, ZrO, SiO2, AlON, AIN, SiON, Si3N4, ZnO, and Ta2O5. The inorganic layers <NUM>, <NUM>, and <NUM> may be formed through chemical vapor deposition ("CVD") or atomic layer deposition ("ALD"). The inorganic layers <NUM>, <NUM>, and <NUM> may block penetration of moisture or oxygen.

The organic layers <NUM> and <NUM> may be formed of a polymer-based material. The polymer-based material may include acrylic resin, epoxy resin, polyimide, polyethylene, and the like, or a combination thereof. The organic layers <NUM> and <NUM> may be formed through a thermal evaporation process.

The thin film encapsulation layer TFE may be formed to a thickness of about <NUM> or less. Accordingly, the overall thickness of the display panel <NUM> may be very thin. As the thin film encapsulation layer TFE may be disposed on the light emitting diode EE, the flexible characteristics of the display panel <NUM> may be improved.

<FIG> is a schematic plan view illustrating an unfolded state of a display device according to another embodiment. <FIG> is a schematic cross-sectional view illustrating a folded state of the display device of <FIG>.

Referring to <FIG>, a display device <NUM> according to another embodiment may include a display module DM, a support member SM, the deco pattern DP, and the set cover SC. However, the deco pattern DP and the set cover SC may be substantially the same as the deco pattern DP and the set cover SC described with reference to <FIG> and <FIG>.

The display module DM may include a first flat portion EP1, a second flat portion EP2, and first to third folding portions FP1, FP2, and FP3 disposed between the first flat portion EP1 and the second flat portion EP2.

In case that the display device <NUM> is folded, the display module DM may be folded so that portions of the display surface S1 face each other. For example, in case that an external force is applied by a user to the display device <NUM> in an unfolded state, the first set cover SC1 may rotate in a clockwise direction, and the second set cover SC2 may rotate in a counterclockwise direction. Accordingly, the display surface S1 of the first flat portion EP1 and the display surface S1 of the second flat portion EP2 may face each other.

In an embodiment, the display module DM may include folding portions. For example, the display module DM may include the first folding portion FP1, the second folding portion FP2, and the third folding portion FP3. The second folding portion FP2 may be disposed between the first flat portion EP1 and the first folding portion FP1, and the first folding portion FP1 may be disposed between the second folding portion FP2 and the third folding portion FP3, and the third folding portion FP3 may be disposed between the first folding portion FP1 and the second flat portion EP2. As the display module DM may include the first to third folding portions FP1, FP2, and FP3, the display module DM may be folded in a dumbbell shape. Accordingly, a curvature of the second folding portion FP2 and a curvature of the third folding portion FP3 may be smaller than a curvature of the first folding portion FP1.

<FIG> is a schematic plan view illustrating an example of a support part (e.g., member) included in the display device of <FIG>.

Referring to <FIG>, and <FIG>, the support member SM may be disposed under the display module DM. The support member SM may be formed of metal and may support the display module SM. For example, the support member SM may include at least one of invar which is an alloy of nickel ("Ni") and iron ("Fe"), stainless steel ("SUS"), titanium ("Ti"), and copper ("Cu").

The support member SM may include a first support portion SP1, a second support portion SP2, first to third lattice portions LP1, LP2, and LP3, a first shape holding portion SHP1, and a second shape holding portion SHP2. In an embodiment, the support member SM may have a structure symmetrical with respect to the first lattice portion LP1. In other words, the second lattice portion LP2 may have substantially the same structure as the third lattice portion LP3, and the first shape holding portion SHP1 may have substantially the same shape as the second shape holding portion SHP2.

In an embodiment, the first support portion SP1 may overlap the first flat portion EP1. Accordingly, the first support portion SP1 may support the first flat portion EP1. The second support portion SP2 may overlap the second flat portion EP2. Accordingly, the second support portion SP2 may support the second flat portion EP2.

In an embodiment, the first to third lattice portions LP1, LP2, and LP3 may overlap the first to third folding portions FP1, FP2, and FP3, respectively. Accordingly, the first to third lattice portions LP1, LP2, and LP3 may support the first to third folding portions FP1, FP2, and FP3, respectively. Holes HL may be formed in each of the first to third lattice portions LP1, LP2, and LP3. The holes HL may penetrate the support member SM in the thickness direction of the support member SM. As the holes HL may penetrate the support member SM, the support member SM may be smoothly folded. Accordingly, the display module DM may be smoothly folded.

In an embodiment, the first shape holding portion SHP1 may be adjacent to the second lattice portion LP2 in the second direction D2 and the fourth direction D4. The second shape holding portion SHP2 may be adjacent to the third lattice portion LP3 in the second direction D2 and the fourth direction D4.

The first and second shape holding portions SHP1 and SHP2 may be disposed to be adjacent to the outermost area of the support member SM, and may overlap the second folding portion FP2 and the third folding portion FP3, respectively. In other words, the first and second shape holding portions SHP1 and SHP2 may overlap the second and third folding portions FP2 and FP3 having relatively small curvatures, respectively. Since the curvature of each of the second and third folding portions FP2 and FP3 may be relatively small, the first and second shape holding portions SHP1 and SHP2 may not be deformed.

In an embodiment, a first boundary hole BHL1 and a second boundary hole BHL2 may be further formed in the second lattice portion LP2. The first and second boundary holes BHL1 and BHL2 may connect the holes HL adjacent to the first shape holding portions SHP1 to each other.

The first boundary hole BHL1 and the second boundary hole BHL2 may define a boundary between the holes HL and the first shape holding portion SHP1. In other words, the first boundary hole BHL1 and the second boundary hole BHL2 may separate the first shape holding portion SHP1 from the holes HL. Accordingly, the first shape holding portion SHP1 may effectively maintain the shape of the support member SM.

<FIG> is a schematic cross-sectional view taken along line V-V' of <FIG>. <FIG> is a schematic cross-sectional view taken along line VI-VI' of <FIG>.

Referring to <FIG>, the display device <NUM> may include the set cover SC, the support member SM, the cushion member CM, the protective film PFL, the display module DM, the deco pattern DP, and the window WIN.

The support member SM may be disposed on the set cover SC. The first and second shape holding portions SHP1 and SHP2 may be disposed to be adjacent to the outermost area of the support member SM. The first lattice portion LP1 may overlap the first folding portion FP1, the first shape holding portion SHP1 may overlap the second folding portion FP2, and the second shape holding portion SHP2 may overlap the third folding portion FP3.

Referring to <FIG>, the support member SM may be disposed on the set cover SC. The first lattice portion LP1 may overlap the first folding portion FP1, the second lattice portion LP2 may overlap the second folding portion FP2, and the third lattice portion LP3 may overlap the third folding portion FP3.

<FIG> is a schematic plan view illustrating another example of a support part (e.g., member) included in the display device of <FIG>.

Referring to <FIG>, the support member SM may include a first support portion SP1, a second support portion SP2, first to third lattice portions LP1, LP2, and LP3, and a first shape holding portion SHP1, and a second shape holding portion SHP2. However, the first support portion SP1, the second support portion SP2, the first lattice portion LP1, the first shape holding portion SHP1, and the second shape holding portion SHP2 may be substantially the same as the first support portion SP1, the second support portion SP2, the first lattice portion LP1, the first shape holding portion SHP1, and the second shape holding portion SHP2 described with reference to <FIG>.

The second and third lattice portions LP2 and LP3 may overlap the second and third folding portions FP2 and FP3, respectively. Accordingly, the second and third lattice portions LP2 and LP3 may support the second and third folding portions FP2 and FP3, respectively.

A first hole HL1 and a second hole HL2 may be formed in the second and third lattice portions LP2 and LP3, respectively. The first hole HL1 and the second hole HL2 may penetrate the support member SM in the thickness direction of the support member SM. As the first and second holes HL1 and HL2 may penetrate the support member SM, the support member SM may be smoothly folded. Accordingly, the display module DM may be smoothly folded.

In an embodiment, a first boundary hole BHL1 and a second boundary hole BHL2 may be further formed in the second lattice portion LP2. The first boundary hole BHL1 and the second boundary hole BHL2 may be connected to (e.g., extended to) the first hole HL1. The first boundary hole BHL1 and the second boundary hole BHL2 may define a boundary between the first hole HL1 and the first shape holding portion SHP1. In other words, the first boundary hole BHL1 and the second boundary hole BHL2 may separate the first shape holding portion SHP1 from the first hole HL. Accordingly, the first shape holding portion SHP1 may effectively maintain the shape of the support member SM. The first boundary hole BHL1 and the second boundary hole BHL2 may not be connected to the second hole HL2.

Display devices <NUM> and <NUM> according to illustrative embodiments may include a display module DM including at least one folding portion FP and a support member SM disposed under the display module DM. The support member SM may include a lattice portion LP overlapping the folding portion FP and a shape holding portion SHP adjacent to the lattice portion LP. The shape holding portion SHP may maintain the shape of the support member SM. For example, the shape holding portion SHP may prevent the lattice portion LP having relatively weak rigidity from being deformed. Accordingly, wrinkles due to folding may not be formed on the upper surfaces of the display devices <NUM> and <NUM>, and the display devices <NUM> and <NUM> may easily perform folding and unfolding.

Claim 1:
A flexible display device (<NUM>) comprising:
a display part (DM) including:
a first flat portion (EP1);
a second flat portion (EP2) spaced apart from the first flat portion (EP1) in a first direction; and
a folding portion (FP) disposed between the first flat portion (EP1) and the second flat portion (EP2);
a support module (SM) disposed under the display part (DM) and including a lattice portion (LP) and a shape holding portion (SHP), and
a boundary hole (BHL1, BHL2) defined in the lattice portion (LP),
wherein
a plurality of holes (HL) extending in a second direction intersecting the first direction are defined in the lattice portion (LP),
the shape holding portion (SHP) is configured to maintain a shape of the support module (SM) and is adjacent to the lattice portion (LP) in the second direction intersecting the first direction and
the lattice portion (LP) and the shape holding portion (SHP) overlap the folding portion (FP),
the plurality of holes (HL) defined in the lattice portion (LP) include a plurality of holes (HL) adjacent to the shape holding portion (SHP), and
the boundary hole (BHL1, BHL2) extends in a direction perpendicular to a direction along which the plurality of holes (HL) extend and is connected to the plurality of holes (HL) adjacent to the shape holding portion (SHP).