Patent Description:
<CIT> describes an adhesive provided by patterning a metal plate with a predetermined elastic modulus, wherein the adhesive is compressively deformed in response to an operation of an adherent to be folded, so that the adhesive can easily return to an original state thereof through formation of a plurality of inner neutral planes upon deformation.

<CIT> describes a foldable backboard structure and display device.

<CIT> describes a foldable electronic paper display device and a manufacturing method of the foldable electronic paper display device.

<CIT> describes a foldable display device.

<CIT> describes a flexible display module.

<CIT> describes a backboard and a display assembly.

<CIT> describes a display apparatus including a display module configured to display an image and to be folded about a folding axis at a folding area defined on a plane, a support member below the display module, and a protective member between the display module and the support member.

Flat panel display devices are used as display devices and replacing a cathode ray tube display device due to lightweight and thin characteristics thereof. Flat panel display devices may include a liquid crystal display device and an organic light emitting diode display device, for example.

Recently, flexible display devices have been developed, in which a lower substrate and an upper substrate of a display panel included the display device may include a flexible material, such that a portion of the display panel may be bent or folded. For example, the lower substrate included in the display panel may be formed of a polyimide substrate, and the upper substrate included in the display panel may have a thin film encapsulation structure. In addition, the flexible display devices may display an image even in a portion where the display panel is folded. In particular, the flexible display device may include a display area, in which an image is displayed, and a portion of the display area may be folded. The flexible display device may further include a support member disposed on a bottom surface of the display panel and including a plurality of openings. The openings of the support member may overlap the portion where the display panel is folded. However, when foreign substances penetrate into the openings while the flexible display device is folded and unfolded, the flexible display device may have defects at the folded portion.

It is the object of the present invention to provide a display device constructed according to exemplary embodiments of the invention that is capable of preventing defects in a foldable area.

This object is achieved by the subject matter of independent claim <NUM>. Preferred embodiments are defined in the sub claims.

Hereinafter, display devices according to exemplary embodiments of the invention will be described in detail with reference to the accompanying drawings. In the accompanying drawings, same or similar reference numerals refer to the same or similar elements.

<FIG> is a plan view of a display device. <FIG> is a perspective view showing a folded shape of a display panel included in the display device of <FIG>. <FIG> is a cross-sectional view taken along line I-I' of <FIG>. <FIG> is an enlarged cross-sectional view showing region A of the display device of <FIG>. For example, <FIG> and <FIG> show a state in which a display device <NUM> is unfolded.

Referring to <FIG>, <FIG>, <FIG>, and <FIG>, the display device <NUM> may include a display panel <NUM>, a shock absorbing member <NUM>, a support member <NUM>, an elastic member <NUM>, a step difference compensation member <NUM>, and the like. In this case, as shown in <FIG>, the display device <NUM> may include a display area <NUM> and a foldable area <NUM>. The display area <NUM> is an area where an image is displayed from the display panel <NUM>, and the foldable area <NUM> is an area where the display device <NUM> is folded or unfolded. A portion of the display area <NUM> may be defined in the foldable area <NUM>. In addition, as shown in <FIG>, the step difference compensation member <NUM> may include a first step difference compensation member <NUM> and a second step difference compensation member <NUM>. Furthermore, as shown in <FIG> and <FIG>, a plurality of openings <NUM>, a plurality of protrusions <NUM>, and a plurality of trenches <NUM> may be formed in the support member <NUM>.

Referring back to <FIG>, <FIG>, and <FIG>, the display panel <NUM> may be provided. The display panel <NUM> may include a plurality of sub-pixels, and may display an image through the sub-pixels. For example, the display panel <NUM> may have a first surface S1 on which an image is displayed, and a second surface S2 facing the first surface S1. In addition, the display panel <NUM> may have a first side surface SS1 and a second side surface SS2 facing the first side surface SS1. As shown in <FIG>, when the display panel <NUM> located in the foldable area <NUM> is folded, the first side surface SS1 and the second side surface SS2 may become adjacent to each other. In addition, the display panel <NUM> located in the foldable area <NUM> may have a curved shape. In this case, the first surface S1 may be located on an inner side, and the second surface S2 may be located on an outer side. Alternatively, in some exemplary embodiments, the display panel <NUM> may be folded, such that the first surface S1 is located on the outer side and the second surface S2 is located on the inner side.

The shock absorbing member <NUM> may be disposed on the second surface S2 of the display panel <NUM>. In particular, the shock absorbing member <NUM> may be disposed between the support member <NUM> and the display panel <NUM>. The shock absorbing member <NUM> may protect the display panel <NUM> from an external impact. In addition, the shock absorbing member <NUM> may include a flexible material so that the display panel <NUM> may be easily folded. For example, the shock absorbing member <NUM> may include a material in the form of a foam, such as a polyurethane foam, a polystyrene foam, or the like.

Referring back to <FIG> and <FIG>, the support member <NUM> may be disposed on a bottom surface of the shock absorbing member <NUM>. In particular, the support member <NUM> may be disposed on the second surface S2 of the display panel <NUM>, and may include a plurality of openings <NUM> formed in the foldable area <NUM>. In the illustrated device, the openings <NUM> may include openings <NUM> arranged in a first direction D1 parallel to a top surface of the display device <NUM>, and openings <NUM> shifted in a second direction D2 orthogonal to the first direction D1 and arranged in the first direction D1. In addition, the support member <NUM> may further include a plurality of protrusions <NUM> protruding in a third direction D3 opposite to the second direction D2. Furthermore, a space between two adjacent protrusions among the protrusions <NUM> may define a trench <NUM>.

For example, the openings <NUM> may include first to nth openings (where n is an integer of <NUM> or more) arranged in the first direction D1, and a kth opening (where k is an even number between <NUM> and n) among the first to nth openings may be located at a position shifted in a second direction perpendicular to the first direction. In addition, the support member <NUM> may further include protrusions <NUM> located in the third direction D3 with respect to each of (k-<NUM>)th and (k+<NUM>)th openings among the first to nth openings, and the trench <NUM> may be defined by the protrusions <NUM>.

The support member <NUM> may support the display panel <NUM>, and may also assist the display panel <NUM> to be folded. For example, the support member <NUM> may be disposed over the second surface S2 of the display panel <NUM> to support the display panel <NUM>, and the openings <NUM> formed in the foldable area <NUM> may assist the display panel <NUM> to be folded. The openings <NUM> may be configured as an empty space. In addition, when the display device <NUM> is folded, a shape of each of the openings <NUM> may be deformed. For example, when each of the openings <NUM> has a geometric shape as illustrated in <FIG>, the support member <NUM> located in the foldable area <NUM> may be deformed in a longitudinal direction (e.g., first direction D1) without being deformed in a depth direction (e.g., a direction from the support member <NUM> toward the display panel <NUM>).

The support member <NUM> may include metal or plastic having a relatively large elastic force or a relatively large restoring force. According to an exemplary embodiment, the support member <NUM> may include steel use stainless (SUS). In some exemplary embodiments, however, the support member <NUM> may include alloys (e.g., superelastic metals), such as nickel-titanium (Ni-Ti), nickel-aluminum (Ni-Al), copper-zinc-nickel (Cu-Zn-Ni), copper-aluminum-nickel (Cu-Al-Ni), copper-aluminum-manganese (Cu-Al-Mn), titanium-nickel-copper-molybdenum (Ti-Ni-Cu-Mo), cobalt-nickel-gallium: iron (Co-Ni-Ga:Fe), silver-nickel (Ag-Ni), gold-cadmium (Au-Cd), iron-platinum (Fe-Pt), iron-nickel (Fe-Ni), and indium-cadmium (In-Cd).

Although each of the openings <NUM> has been described as having a rectangular shape when viewed in a plan view, the inventive concepts are not limited to a particular shape of each of the openings <NUM>. For example, each of the openings <NUM> may have substantially a triangular shape, a rhombic shape, a polygonal shape, a circular shape, a track shape, or an elliptical shape, when viewed from a plan view.

The elastic member <NUM> may be disposed at a portion of a bottom surface of the support member <NUM>. In particular, the elastic member <NUM> may overlap the openings <NUM> in the foldable area <NUM> on the bottom surface of the support member <NUM>. As such, the elastic member <NUM> may prevent the openings <NUM> from being exposed. According to an exemplary embodiment, the elastic member <NUM> may not be disposed inside each of the openings <NUM>, such that the openings <NUM> may be configured as empty spaces. While the display device <NUM> is repeatedly folded and unfolded, the elastic member <NUM> may prevent foreign substances from penetrating into the openings <NUM> and the trench <NUM>. In addition, while the display device <NUM> is repeatedly folded and unfolded, the elastic member <NUM> may be extended and contracted to prevent the openings <NUM> from being exposed. The elastic member <NUM> may include an elastomer having a relatively large elastic force or a relatively large restoring force. For example, the elastic member <NUM> may include an elastic material, such as silicone, urethane, or thermoplastic polyurethane (TPU).

For example, when a conventional display device is repeatedly folded and unfolded, foreign substances may penetrate into the openings <NUM>. The penetrated foreign substances may not escape out of the openings <NUM>. In this case, due to the foreign substances, the support member <NUM> located in the foldable area <NUM> may be damaged, or the shapes of the openings <NUM> may be deformed, which may cause defects in the foldable area <NUM> of the conventional display device.

According to an exemplary embodiment, the elastic member <NUM> is disposed on the openings <NUM> to prevent the openings <NUM> from being exposed to prevent the foreign substances from being located in the openings <NUM>.

The step difference compensation member <NUM> may be disposed on the bottom surface of the support member <NUM> while being spaced apart from the elastic member <NUM>. For example, the first step difference compensation member <NUM> may be disposed at a first portion on the bottom surface of the support member <NUM>, and the second step difference compensation member <NUM> may be disposed at a second portion on the bottom surface of the support member <NUM>. According to an exemplary embodiment, a bottom surface of the step difference compensation member <NUM> may be located at the same level as a bottom surface of the elastic member <NUM>. The step difference compensation member <NUM> may prevent the display panel <NUM> from sagging at a portion where the elastic member <NUM> is not disposed. The step difference compensation member <NUM> may include polyethylene terephthalate (PET), polyethylene naphthalene (PEN), polypropylene (PP), polycarbonate (PC), polystyrene (PS), polysulfone (PSul), polyethylene (PE), polyphthalamide (PPA), polyether sulfone (PES), polyarylate (PAR), polycarbonate oxide (PCO), modified polyphenylene oxide (MPPO), etc..

The display device <NUM> includes the elastic member <NUM> disposed on the openings <NUM> to prevent the openings <NUM> from being exposed, such that the foreign substances may not be located in the openings <NUM>. In this manner, defects may not occur in the foldable area <NUM> of the display device.

<FIG> is an enlarged cross-sectional view showing region B of the display device of <FIG>.

The display panel <NUM> may include a substrate <NUM>, a semiconductor element <NUM>, a planarization layer <NUM>, a lower electrode <NUM>, a pixel defining layer <NUM>, a light emitting layer <NUM>, an upper electrode <NUM>, a first thin film encapsulation layer <NUM>, a second thin film encapsulation layer <NUM>, a third thin film encapsulation layer <NUM>, and the like. The semiconductor element <NUM> may include an active layer <NUM>, a gate insulating layer <NUM>, a gate electrode <NUM>, an interlayer insulating layer <NUM>, a source electrode <NUM>, and a drain electrode <NUM>.

The substrate <NUM> may include a transparent or opaque material. In some exemplary embodiments, the substrate <NUM> may be disposed on a lower protective film. The substrate <NUM> may be formed of a transparent resin substrate, such as a polyimide substrate. In this case, the polyimide substrate may include a first polyimide layer, a barrier film layer, a second polyimide layer, and the like. In other exemplary embodiments, the substrate <NUM> may include a quartz substrate, a synthetic quartz substrate, a calcium fluoride substrate, a fluorine-doped quartz substrate (F-doped quartz substrate), a soda lime glass substrate, a non-alkali glass substrate, etc..

A buffer layer may be disposed on the substrate <NUM>. The buffer layer may prevent metal atoms or impurities from diffusing from the substrate <NUM> to the semiconductor element <NUM>, and may control a heat transfer rate during a crystallization process for forming the active layer <NUM> to obtain a substantially uniform active layer <NUM>. In addition, when a surface of the substrate <NUM> is not uniform, the buffer layer may improve flatness of the surface of the substrate <NUM>. Depending on a type of the substrate <NUM>, at least two buffer layers may be provided on the substrate <NUM>, or the buffer layer may be omitted. For example, the buffer layer may include an organic material or an inorganic material.

The active layer <NUM> may be disposed on the substrate <NUM>. The active layer <NUM> may include a metal oxide semiconductor, an inorganic semiconductor (e.g., amorphous silicon or poly silicon semiconductor), an organic semiconductor, etc. The active layer <NUM> may have source and drain regions.

The gate insulating layer <NUM> may be disposed on the active layer <NUM>. For example, the gate insulating layer <NUM> may sufficiently cover the active layer <NUM> on the substrate <NUM>, and may have a substantially flat top surface without creating a step around the active layer <NUM>. In some exemplary embodiments, the gate insulating layer <NUM> may be disposed along a profile of the active layer <NUM> with a substantially uniform thickness to cover the active layer <NUM> on the substrate <NUM>. The gate insulating layer <NUM> may include a silicon compound, metal oxide, etc. For example, the gate insulating layer <NUM> may include silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), silicon oxycarbide (SiOxCy), silicon carbonitride (SiCxNy), aluminum oxide (AlOx), aluminum nitride (AlNx), tantalum oxide (TaOx), hafnium oxide (HfOx), zirconium oxide (ZrOx), titanium oxide (TiOx), etc. In other exemplary embodiments, the gate insulating layer <NUM> may have a multilayer structure including a plurality of insulating layers. For example, the insulating layers may have different thicknesses and/or may include different materials.

The gate electrode <NUM> may be disposed on the gate insulating layer <NUM>. The gate electrode <NUM> may be disposed at a portion of the gate insulating layer <NUM>, under which the active layer <NUM> is located. The gate electrode <NUM> may include metal, an alloy, metal nitride, conductive metal oxide, a transparent conductive material, etc. For example, the gate electrode <NUM> may include gold (Au), silver (Ag), aluminum (Al), tungsten (W), copper (Cu), platinum (Pt), nickel (Ni), titanium (Ti), palladium (Pd), magnesium (Mg), calcium (Ca), lithium (Li), chromium (Cr), tantalum (Ta), molybdenum (Mo), scandium (Sc), neodymium (Nd), iridium (Ir), an aluminum-containing alloy, aluminum nitride (AlNx), a silver-containing alloy, tungsten nitride (WNx), a copper-containing alloy, a molybdenum-containing alloy, titanium nitride (TiNx), chromium nitride (CrNx), tantalum nitride (TaNx), strontium ruthenium oxide (SrRuxOy), zinc oxide (ZnOx), indium tin oxide (ITO), tin oxide (SnOx), indium oxide (InOx), gallium oxide (GaOx), indium zinc oxide (IZO), etc. These may be used alone or in combination with each other. In other exemplary embodiments, the gate electrode <NUM> may have a multilayer structure including a plurality of metal layers. For example, the metal layers may have different thicknesses and/or may include different materials.

The interlayer insulating layer <NUM> may be disposed on the gate electrode <NUM>. The interlayer insulating layer <NUM> may sufficiently cover the gate electrode <NUM> on the gate insulating layer <NUM>, and may have a substantially flat top surface without creating a step around the gate electrode <NUM>. In some exemplary embodiments, the interlayer insulating layer <NUM> may be disposed along a profile of the gate electrode <NUM> with a substantially uniform thickness to cover the gate electrode <NUM> on the gate insulating layer <NUM>. The interlayer insulating layer <NUM> may include a silicon compound, metal oxide, etc. In some exemplary embodiments, the interlayer insulating layer <NUM> may have a multilayer structure including a plurality of insulating layers. For example, the insulating layers may have different thicknesses and/or may include different materials.

The source electrode <NUM> and the drain electrode <NUM> may be disposed on the interlayer insulating layer <NUM>. The source electrode <NUM> may be connected to the source region of the active layer <NUM> through a contact hole formed by removing first parts of the gate insulating layer <NUM> and the interlayer insulating layer <NUM>, and the drain electrode <NUM> may be connected to the drain region of the active layer <NUM> through a contact hole formed by removing second parts of the gate insulating layer <NUM> and the interlayer insulating layer <NUM>. Each of the source electrode <NUM> and the drain electrode <NUM> may include metal, an alloy, metal nitride, conductive metal oxide, a transparent conductive material, etc. These may be used alone or in combination with each other. In other exemplary embodiments, each of the source electrode <NUM> and the drain electrode <NUM> may have a multilayer structure including a plurality of metal layers. For example, the metal layers may have different thicknesses and/or may include different materials.

Accordingly, the semiconductor element <NUM> including the active layer <NUM>, the gate insulating layer <NUM>, the gate electrode <NUM>, the interlayer insulating layer <NUM>, the source electrode <NUM>, and the drain electrode <NUM> may be provided.

Although the semiconductor element <NUM> has been described as having a top gate structure, the inventive concept are not limited thereto. For example, in some exemplary embodiments, the semiconductor element <NUM> may have a bottom gate structure, a double gate structure, etc..

In addition, although the display device <NUM> has been described as including one semiconductor element, the inventive concepts are not limited thereto. For example, the display device <NUM> may include at least one semiconductor element and at least one storage capacitor.

The planarization layer <NUM> may be disposed on the interlayer insulating layer <NUM>, the source electrode <NUM>, and the drain electrode <NUM>. For example, the planarization layer <NUM> may have a relatively thick thickness. In this case, the planarization layer <NUM> may have a substantially flat top surface. In order to implement such a flat top surface of the planarization layer <NUM>, a planarization process may be additionally performed on the planarization layer <NUM>. In some exemplary embodiments, the planarization layer <NUM> may be disposed along a profile of the source electrode <NUM> and the drain electrode <NUM> with a substantially uniform thickness on the interlayer insulating layer <NUM>. The planarization layer <NUM> may be formed of an organic material or an inorganic material. In an exemplary embodiment, the planarization layer <NUM> may include an organic material. For example, the planarization layer <NUM> may include a photoresist, a polyacryl-based resin, a polyimide-based resin, a polyamide-based resin, a siloxane-based resin, an acryl-based resin, an epoxy-based resin, etc..

The lower electrode <NUM> may be disposed on the planarization layer <NUM>. The lower electrode <NUM> may be connected to the drain electrode <NUM> through a contact hole formed by removing a portion of the planarization layer <NUM>, such that the lower electrode <NUM> may be electrically connected to the semiconductor element <NUM>. The lower electrode <NUM> may include metal, an alloy, metal nitride, conductive metal oxide, a transparent conductive material, etc. These may be used alone or in combination with each other. In other exemplary embodiments, the lower electrode <NUM> may have a multilayer structure including a plurality of metal layers. For example, the metal layers may have different thicknesses and/or may include different materials.

The pixel defining layer <NUM> may be disposed on the planarization layer <NUM>. For example, the pixel defining layer <NUM> may expose a portion of a top surface of the lower electrode <NUM> while covering both sides of the lower electrode <NUM>. The pixel defining layer <NUM> may be formed of an organic material or an inorganic material. In the illustrated exemplary embodiment, the pixel defining layer <NUM> may include an organic material.

The light emitting layer <NUM> may be disposed on the pixel defining layer <NUM> and the lower electrode <NUM>. The light emitting layer <NUM> may be formed by using at least one of light emitting materials for emitting different colors of light (e.g., red light, green light, blue light, etc.) according to sub-pixels. Alternatively, the light emitting layer <NUM> may be formed by laminating a plurality of light emitting materials for emitting different colors of light, such as red light, green light, and blue light to emit white light as a whole. In this case, a color filter may be disposed on the light emitting layer <NUM> that is disposed on the lower electrode <NUM>. The color filter may include at least one of a red color filter, a green color filter, and a blue color filter. In some exemplary embodiments, the color filter may include a yellow color filter, a cyan color filter, and a magenta color filter, for example. The color filter may include a photosensitive resin or a color photoresist.

The upper electrode <NUM> may be disposed on the light emitting layer <NUM> and the pixel defining layer <NUM>. The upper electrode <NUM> may include metal, an alloy, metal nitride, conductive metal oxide, a transparent conductive material, etc. These may be used alone or in combination with each other. In other exemplary embodiments, the upper electrode <NUM> may have a multilayer structure including a plurality of metal layers. For example, the metal layers may have different thicknesses and/or may include different materials.

The first thin film encapsulation layer <NUM> may be disposed on the upper electrode <NUM>. The first thin film encapsulation layer <NUM> may be disposed along a profile of the upper electrode <NUM> with a substantially uniform thickness to cover the upper electrode <NUM>. The first thin film encapsulation layer <NUM> may prevent the light emitting layer <NUM> from being deteriorated due to penetration of moisture, oxygen, or the like. In addition, the first thin film encapsulation layer <NUM> may also protect the display panel <NUM> from an external impact. The first thin film encapsulation layer <NUM> may include inorganic materials having flexibility.

The second thin film encapsulation layer <NUM> may be disposed on the first thin film encapsulation layer <NUM>. The second thin film encapsulation layer <NUM> may improve flatness of the display panel <NUM> and protect the display panel <NUM>. The second thin film encapsulation layer <NUM> may include organic materials having flexibility.

The third thin film encapsulation layer <NUM> may be disposed on the second thin film encapsulation layer <NUM>. The third thin film encapsulation layer <NUM> may be disposed along a profile of the second thin film encapsulation layer <NUM> with a substantially uniform thickness to cover the second thin film encapsulation layer <NUM>. The third thin film encapsulation layer <NUM> may prevent the light emitting layer <NUM> from being deteriorated due to the penetration of moisture, oxygen, or the like together with the first thin film encapsulation layer <NUM>. In addition, the third thin film encapsulation layer <NUM> may also protect the display panel <NUM> from an external impact together with the first thin film encapsulation layer <NUM> and the second thin film encapsulation layer <NUM>. The third thin film encapsulation layer <NUM> may include inorganic materials having flexibility.

Accordingly, the display panel <NUM> including the substrate <NUM>, the semiconductor element <NUM>, the planarization layer <NUM>, the lower electrode <NUM>, the pixel defining layer <NUM>, the light emitting layer <NUM>, the upper electrode <NUM>, the first thin film encapsulation layer <NUM>, the second thin film encapsulation layer <NUM>, and the third thin film encapsulation layer <NUM> may be provided.

Although the display device <NUM> according to the illustrated exemplary embodiment has been described as being an organic light emitting diode display device, the inventive concepts are not limited thereto. In other exemplary embodiments, the display device <NUM> may include a liquid crystal display device (LCD), a field emission display device (FED), a plasma display device (PDP), or an electrophoretic image display device (EPD).

<FIG> is a cross-sectional view of a display device according to an embodiment. A display device <NUM> illustrated in <FIG> may have a configuration substantially identical or similar to the configuration of the display device <NUM> described with reference to <FIG>, except for a first adhesive member <NUM>, a second adhesive member <NUM>, a third adhesive member <NUM>, a fourth adhesive member <NUM>, a fifth adhesive member <NUM>, and a metal member <NUM>. As such, repeated descriptions of components substantially identical or similar to the components described with reference to <FIG> will be omitted to avoid redundancy. For example, <FIG> shows a state in which the display device <NUM> is unfolded.

Referring to <FIG>, the display device <NUM> may include a display panel <NUM>, a third adhesive member <NUM>, a shock absorbing member <NUM>, a second adhesive member <NUM>, a support member <NUM>, a first adhesive member <NUM>, an elastic member <NUM>, a fourth adhesive member <NUM>, a fifth adhesive member <NUM>, a metal member <NUM>, and a step difference compensation member <NUM>. The display device <NUM> may include a display area <NUM> and a foldable area <NUM>. The display area <NUM> is an area where an image is displayed from the display panel <NUM>, and the foldable area <NUM> is an area where the display device <NUM> is folded or unfolded. A portion of the display area <NUM> may be defined as the foldable area <NUM>. In addition, the step difference compensation member <NUM> may include a first step difference compensation member <NUM> and a second step difference compensation member <NUM>, and the metal member <NUM> may include a first metal member <NUM> and a second metal member <NUM>. Furthermore, a plurality of openings <NUM>, a plurality of protrusions <NUM>, and a plurality of trenches <NUM> may be formed in the support member <NUM>.

The first adhesive member <NUM> may be disposed between the support member <NUM> and the elastic member <NUM>. In the illustrated embodiment, a top surface of the first adhesive member <NUM> may make direct contact with the support member <NUM>, and a bottom surface of the first adhesive member <NUM> may make direct contact with the elastic member <NUM>. In addition, the first adhesive member <NUM> may cover the openings <NUM>. The first adhesive member <NUM> may attach the elastic member <NUM> onto the bottom surface of the support member <NUM>. In the illustrated embodiment, the first adhesive member <NUM> may not be disposed inside each of the openings <NUM>, such that the openings <NUM> may be configured as empty spaces. While the display device <NUM> is repeatedly folded and unfolded, the first adhesive member <NUM> may prevent foreign substances from penetrating into the openings <NUM> and the trench <NUM> together with the elastic member <NUM>. In addition, while the display device <NUM> is repeatedly folded and unfolded, the first adhesive member <NUM> may be extended and contracted to prevent the openings <NUM> from being exposed.

The first adhesive member <NUM> may include an optical clear adhesive (OCA), a pressure sensitive adhesive (PSA), a photocurable resin, a thermosetting resin, etc. For example, the adhesive may include PET, PEN, PP, PC, PS, PSul, PE, PPA, PES, PAR, PCO, MPPO, and the like, and the resin may include an epoxy resin, an amino resin, a phenol resin, a urea resin, a melamine resin, an unsaturated polyester resin, a polyurethane resin, a polyimide resin, and the like.

The second adhesive member <NUM> may be disposed between the shock absorbing member <NUM> and the support member <NUM>. In the exemplary embodiments, a top surface of the second adhesive member <NUM> may make direct contact with the shock absorbing member <NUM>, and a bottom surface of the second adhesive member <NUM> may make direct contact with the support member <NUM>. In addition, the second adhesive member <NUM> may cover the openings <NUM>. The second adhesive member <NUM> may adhere the shock absorbing member <NUM> onto a top surface of the support member <NUM>. In the exemplary embodiments, the second adhesive member <NUM> may not be disposed inside each of the openings <NUM> such that the openings <NUM> may be configured as empty spaces. The second adhesive member <NUM> may include an OCA, a PSA, a photocurable resin, a thermosetting resin, etc..

The third adhesive member <NUM> may be disposed between the display panel <NUM> and the shock absorbing member <NUM>. In the exemplary embodiments, a top surface of the third adhesive member <NUM> may make direct contact with the display panel <NUM>, and a bottom surface of the third adhesive member <NUM> may make direct contact with the shock absorbing member <NUM>. In addition, the third adhesive member <NUM> may adhere the display panel <NUM> to the shock absorbing member <NUM>. The third adhesive member <NUM> may include an OCA, a PSA, a photocurable resin, a thermosetting resin, etc..

The metal member <NUM> may be disposed on the bottom surface of the elastic member <NUM>. For example, the first metal member <NUM> may be disposed at a first portion on the bottom surface of the elastic member <NUM>, and the second metal member <NUM> may be disposed at a second portion of the bottom surface of the elastic member <NUM>. In this case, each of the first and second portions of the elastic member <NUM> may partially overlap the foldable area <NUM>. In the embodiments, the first metal member <NUM> and the second metal member <NUM> may be spaced apart from each other in the first direction D1. A spaced distance may be determined according to the radius of curvature of the foldable area <NUM>. In the embodiments, the metal member <NUM> may prevent the display panel <NUM> from sagging in the foldable area <NUM>, and may serve to block static electricity, electromagnetic waves, electric fields, magnetic fields, and the like which are generated from an outside. The metal member <NUM> may include SUS. In some embodiments, the metal member may include Au, Ag, Al, W, Cu, Pt, Ni, Ti, Pd, Mg, Ca, Li, Cr, Ta, Mo, Sc, Nd, Ir, an aluminum-containing alloy, AlNx, a silver-containing alloy, WNx, a copper-containing alloy, a molybdenum-containing alloy, TiNx, CrNx, TaNx, SrRuxOy, ZnOx, ITO, SnOx, InOx, GaOx, IZO, etc. These may be used alone or in combination with each other. In other exemplary embodiments, a step difference compensation member and an adhesive member may be additionally disposed on a bottom surface of the metal member <NUM>. The adhesive member may make contact with a set member surrounding the display device <NUM>, and the step difference compensation member may prevent the display panel <NUM> from sagging in the foldable area <NUM> together with the metal member <NUM>.

The fourth adhesive member <NUM> may be disposed between the first metal member <NUM> and the elastic member <NUM>. In the embodiments, a top surface of the fourth adhesive member <NUM> may make direct contact with the elastic member <NUM>, and a bottom surface of the fourth adhesive member <NUM> may make direct contact with the first metal member <NUM>. The fourth adhesive member <NUM> may adhere the first metal member <NUM> to the first portion on the bottom surface of the elastic member <NUM>. The fifth adhesive member <NUM> may be disposed between the second metal member <NUM> and the elastic member <NUM>. In the exemplary embodiments, a top surface of the fifth adhesive member <NUM> may make direct contact with the elastic member <NUM>, and a bottom surface of the fifth adhesive member <NUM> may make direct contact with the second metal member <NUM>. In addition, the fourth adhesive member <NUM> and the fifth adhesive member <NUM> may be spaced apart from each other in the first direction D1. The fifth adhesive member <NUM> may adhere the second metal member <NUM> to the second portion on the bottom surface of the elastic member <NUM>. Each of the fourth adhesive member <NUM> and the fifth adhesive member <NUM> may include an OCA, a PSA, a photocurable resin, a thermosetting resin, etc..

In other embodiments, a first step difference compensation member may be additionally disposed at the first portion on the bottom surface of the elastic member <NUM> together with the fourth adhesive member <NUM>, and a second step difference compensation member may be additionally disposed at the second portion on the bottom surface of the elastic member <NUM> together with the fifth adhesive member <NUM>. The first and second step difference compensation members may prevent the display panel <NUM> from sagging in the foldable area <NUM>.

The step difference compensation member <NUM> may be spaced apart from the first adhesive member <NUM>, the elastic member <NUM>, the fourth adhesive member <NUM>, and the metal member <NUM> on the bottom surface of the support member <NUM>. For example, the first step difference compensation member <NUM> may be disposed at the first portion on the bottom surface of the support member <NUM>, and the second step difference compensation member <NUM> may be disposed at the second portion on the bottom surface of the support member <NUM>. In the embodiments, the bottom surface of the step difference compensation member <NUM> may be located at the same level as the bottom surface of the metal member <NUM>. The step difference compensation member <NUM> may prevent the display panel <NUM> from sagging in a portion where the metal member <NUM> is not disposed. The step difference compensation member <NUM> may include PET, PEN, PP, PC, PS, PSul, PE, PPA, PES, PAR, PCO, MPPO, etc. In other embodiments, an additional adhesive member may be disposed on the bottom surface of the step difference compensation member <NUM> to make contact with a set member surrounding the display device <NUM>.

The display device <NUM> according to an embodiment includes the elastic member <NUM> disposed on the openings <NUM> to prevent the openings <NUM> from being exposed, so that the foreign substances may not be located in the openings <NUM>. In this manner, defects may not occur in the foldable area <NUM> of the display device <NUM>.

In addition, the display device <NUM> includes the metal member <NUM>, so that the display panel <NUM> may be prevented from sagging in the foldable area <NUM>, and static electricity, electromagnetic waves, electric fields, magnetic fields, and the like, which may be generated from the outside, may be blocked.

<FIG> is a plan view of a display device according to an embodiment, <FIG> is a plan view showing a rear side of the display device of <FIG>, and <FIG> is a side view showing a lateral side of the display device of <FIG>. A display device <NUM> illustrated in <FIG>, <FIG>, and <FIG> may have a configuration substantially identical or similar to the configuration of the display device <NUM> described with reference to <FIG>, except for an elastic member <NUM>. As such, repeated descriptions of components substantially identical or similar to the components described with reference to <FIG> will be omitted to avoid redundancy. For example, <FIG>, <FIG>, and <FIG> show a state in which the display device <NUM> is unfolded.

Referring to <FIG>, <FIG>, and <FIG>, the display device <NUM> may include a display panel <NUM>, a shock absorbing member <NUM>, a support member <NUM>, an elastic member <NUM>, and a step difference compensation member <NUM>. In this case, the display device <NUM> may include a display area <NUM> and a foldable area <NUM>. The display area <NUM> is an area where an image is displayed from the display panel <NUM>, and the foldable area <NUM> is an area where the display device <NUM> is folded or unfolded. A portion of the display area <NUM> may be defined as the foldable area <NUM>. In addition, the step difference compensation member <NUM> may include a first step difference compensation member <NUM> and a second step difference compensation member <NUM>. Furthermore, a plurality of openings <NUM>, a plurality of protrusions <NUM>, and a plurality of trenches <NUM> may be formed in the support member <NUM>.

The elastic member <NUM> may be disposed at a portion of the bottom surface of the support member <NUM> and a portion of a side surface of the support member <NUM>. In particular, the elastic member <NUM> may overlap the trenches <NUM> in the foldable area <NUM> on the side surface of the support member <NUM>, while overlapping the openings <NUM> in the foldable area <NUM> on the bottom surface of the support member <NUM>. In this manner, the elastic member <NUM> may prevent the openings <NUM> and the trenches <NUM> from being exposed. In the illustrated embodiment, the elastic member <NUM> may not be disposed inside each of the openings <NUM> and the trenches <NUM>, such that the openings <NUM> and the trenches <NUM> may be configured as empty spaces. While the display device <NUM> is repeatedly folded and unfolded, the elastic member <NUM> may prevent foreign substances from penetrating into the openings <NUM> and the trenches <NUM>. In addition, while the display device <NUM> is repeatedly folded and unfolded, the elastic member <NUM> may be extended and contracted to prevent the openings <NUM> and the trenches <NUM> from being exposed. The elastic member <NUM> may include an elastomer having a relatively large elastic force or a relatively large restoring force. For example, the elastic member <NUM> may include an elastic material, such as silicone, urethane, or TPU.

The display device <NUM> according to the illustrated embodiment includes the elastic member <NUM>, so that the openings <NUM> and the trenches <NUM> of the support member <NUM> may be covered to prevent the foreign substances from being located in the openings <NUM> and the trenches <NUM>. Accordingly, defects due to the foreign substances may not occur in the display device <NUM>.

The inventive concepts may be applied to various electronic devices including a display device. For example, the inventive concepts may be applied to a vehicle-display device, a ship-display device, an aircraft-display device, portable communication devices, display devices for display or for information transfer, a medical-display device, etc..

As the display device according to the embodiments includes the elastic member disposed on the openings to prevent the openings from being exposed, the foreign substances may not be located in the openings. Accordingly, defects may not occur in the foldable area of the display device.

In addition, as the display device includes the metal member, the display panel may be prevented from sagging in the foldable area, and static electricity, electromagnetic waves, electric fields, magnetic fields, and the like, which may be generated from the outside, may be blocked.

Claim 1:
A display device (<NUM>) comprising:
a display panel (<NUM>) having a foldable area (<NUM>);
a support member (<NUM>) disposed on a bottom surface of the display panel (<NUM>) and including a plurality of openings (<NUM>) formed in the foldable area (<NUM>); and
an elastic member (<NUM>) disposed on a bottom surface of the support member (<NUM>) and overlapping the openings (<NUM>) in the foldable area (<NUM>)
characterized in that
the display device (<NUM>) further comprises:
a first metal member (<NUM>) disposed at a first portion on a bottom surface of the elastic member (<NUM>); and
a second metal member (<NUM>) disposed at a second portion on the bottom surface of the elastic member (<NUM>) while being spaced apart from the first metal member (<NUM>),
wherein each of the first and second portions partially overlaps the foldable area (<NUM>).