Patent ID: 12225673

DETAILED DESCRIPTIONS

Advantages and features of the present disclosure, and how to achieve them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present disclosure is not limited to the embodiments as disclosed below, but will be implemented in a variety of different forms. Only these embodiments make the present disclosure complete, and are constructed to fully inform those having common knowledge in the technical field to which the present disclosure belongs of a scope of the disclosure. The scope of the present disclosure is only defined by the scope of the claims.

A shape, a size, a ratio, an angle, a number, etc. disclosed in the drawings for illustrating embodiments of the present disclosure are exemplary, and the present disclosure is not limited thereto. The same reference numerals refer to the same elements herein. Further, in describing the present disclosure, when it is determined that a detailed description of a related known element may unnecessarily obscure gist of the present disclosure, the detailed description thereof will be omitted. As used herein, the singular forms “a” and “an” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “includes”, and “including” when used in this specification, specify the presence of the stated features, integers, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, operations, elements, components, and/or portions thereof.

In interpreting a numerical value, the value is interpreted as including an error range unless there is no separate explicit description thereof.

It will be understood that when an element or layer is referred to as being “connected to”, or “coupled to” another element or layer, it may be directly on, connected to, or coupled to the other element or layer, or one or more intervening elements or layers may be present. In addition, it will also be understood that when an element or layer is referred to as being “between” two elements or layers, it may be the only element or layer between the two elements or layers, or one or more intervening elements or layers may also be present. In addition, it will also be understood that when a first element or layer is referred to as being present “on” or “beneath” a second element or layer, the first element may be disposed directly on or beneath the second element or may be disposed indirectly on or beneath the second element with a third element or layer being disposed between the first and second elements or layers.

Further, as used herein, when a layer, film, region, plate, or the like is disposed “on” or “on a top” of another layer, film, region, plate, or the like, the former may directly contact the latter or still another layer, film, region, plate, or the like may be disposed between the former and the latter. As used herein, when a layer, film, region, plate, or the like is directly disposed “on” or “on a top” of another layer, film, region, plate, or the like, the former directly contacts the latter and still another layer, film, region, plate, or the like is not disposed between the former and the latter. Further, as used herein, when a layer, film, region, plate, or the like is disposed “below” or “under” another layer, film, region, plate, or the like, the former may directly contact the latter or still another layer, film, region, plate, or the like may be disposed between the former and the latter. As used herein, when a layer, film, region, plate, or the like is directly disposed “below” or “under” another layer, film, region, plate, or the like, the former directly contacts the latter and still another layer, film, region, plate, or the like is not disposed between the former and the latter.

In descriptions of temporal relationships, for example, temporal precedent relationships between two events such as “after”, “subsequent to”, “before”, etc., another event may occur therebetween unless “directly after”, “directly subsequent” or “directly before” is not indicated.

It will be understood that, although the terms “first”, “second”, “third”, and so on may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section described below could be termed a second element, component, region, layer or section, without departing from the spirit and scope of the present disclosure.

The features of the various embodiments of the present disclosure may be partially or entirely combined with each other, and may be technically associated with each other or operate with each other. The embodiments may be implemented independently of each other and may be implemented together in an association relationship.

In descriptions of temporal relationships, for example, temporal precedent relationships between two events such as “after”, “subsequent to”, “before”, etc., another event may occur therebetween unless “directly after”, “directly subsequent” or “directly before” is not indicated. The features of the various embodiments of the present disclosure may be partially or entirely combined with each other, and may be technically associated with each other or operate with each other. The embodiments may be implemented independently of each other and may be implemented together in an association relationship. Spatially relative terms, such as “beneath,” “below,” “lower,” “under,” “above,” “upper,” and the like, may be used herein for ease of explanation to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the apparatus in use or in operation, in addition to the orientation depicted in the figures. For example, when the apparatus in the drawings may be turned over, elements described as “below” or “beneath” or “under” other elements or features would then be oriented “above” the other elements or features. Thus, the example terms “below” and “under” may encompass both an orientation of above and below. The apparatus may be otherwise oriented for example, rotated 90 degrees or at other orientations, and the spatially relative descriptors used herein should be interpreted accordingly.

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 this inventive concept belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

In the present disclosure, a “display apparatus” may include display apparatus in a narrow sense, such as a liquid crystal module (LCM), an organic light-emitting module (OLED) module, and a quantum dot module, including a display panel and a driver for driving the display panel. Moreover, the “display apparatus” may also include a set electronic apparatus or a set apparatus such as a laptop computer, a television, and a computer monitor, an equipment display including an automotive display or displays of other types of a vehicle, a mobile electronic apparatus such as a smartphone or an electronic pad, and the like, which are complete products (or final products) including an LCM, an OLED module, a QD module, and the like.

Therefore, the display apparatus in the present disclosure may not only include the display apparatus itself in the narrow sense such as the LCM, the OLED module, the QD module, and the like, but also include the set apparatus, which is an applied product or an end-user apparatus, including the LCM, the OLED module, the QD module, and the like.

Moreover, in some cases, the LCM, the OLED module, and the QD module composed of the display panel, the driver, and the like may be expressed as the “display apparatus” in the narrow sense, and the electronic apparatus as the complete product including the LCM, the OLED module, and the QD module may be expressed as the “set apparatus”. For example, the display apparatus in the narrow sense may include a liquid crystal (LCD), organic light-emitting (OLED), or quantum dot display panel, and a source PCB that is a controller for driving the display panel, and the set apparatus may be a concept that further includes a set PCB, which is a set controller that is electrically connected to the source PCB and controls the entire set apparatus.

The display panel used in the present embodiment may be any type of display panel such as a liquid crystal display panel, an organic light-emitting diode (OLED) display panel, a quantum dot (QD) display panel, an electroluminescent display panel, and the like, and may not be limited to a specific display panel capable of bezel bending with a flexible substrate for the organic light-emitting diode (OLED) display panel of the present embodiment and a lower backplate support structure. Moreover, the display panel used in the display apparatus according to an embodiment of the present disclosure is not limited in a shape or a size.

More specifically, when the display panel is the organic light-emitting diode (OLED) display panel, the display panel may include a plurality of gate lines and data lines, and pixels formed in intersection areas of the gate lines and the data lines. Moreover, the display panel may include an array including a thin-film transistor, which is an element for selectively applying a voltage to each pixel, an organic light-emitting element (OLED) layer on the array, and an encapsulation substrate or an encapsulation layer disposed on the array to cover the organic light-emitting element layer. The encapsulation layer may protect a thin-film transistor, the organic light-emitting element layer, and the like from an external impact, and may prevent penetration of moisture or oxygen into the organic light-emitting element layer. Moreover, a layer formed on the array may include an inorganic light emitting layer, for example, a nano-sized material layer or a quantum dot.

In the present disclosure,FIG.1shows a foldable display apparatus10to which an embodiment of the present disclosure is applied such that the apparatus is folded in an in-folding manner and at the same time, slides to enlarge a display area.

Referring toFIG.1, because the display apparatus must be foldable or slidable, an organic light-emitting diode display (OLED) panel100may be applied as a display panel100.

FIG.1illustrates the exemplary organic light-emitting diode display (OLED) panel100that may be integrated into the display apparatus. The organic light-emitting diode display panel100, which is a self-luminous display element that does not require a separate light source, may be manufactured to be thin, and may be recently manufactured by manufacturing a glass substrate, which was used as a substrate for a display element, to be extremely thin or actively utilizing a plastic substrate to be actively used in a foldable display apparatus that may be folded or rolled,

Referring toFIG.1, it may be seen that, at the same time when the display apparatus10is folded at a certain angle around a hinge, a display area is expanded to become large in an upper portion of the hinge and the display area is reduced to become small in a lower portion of the hinge.

FIG.2is a conceptual diagram showing components of the display apparatus10according to an embodiment of the present disclosure in an exploded manner.

Referring toFIG.2, a bottom plate210, a top plate220, a back plate230, the display panel100, a polarizing film240, and a cover window250are sequentially arranged based on a back face of the display apparatus10.

First, the bottom plate210and the top plate220may be made of a light and transparent material such as polyethylene terephthalate (PET).

The bottom plate210may be disposed on the lowest layer and support the display panel100while in direct contact with a module of the display apparatus10. A perforated hole (not shown) may be defined in an area of the bottom plate210adjacent to the hinge to facilitate a folding operation. Because the polyethylene terephthalate is a hard material with elasticity at a certain thickness, the definition of the perforated hole may be a method to maintain a constant folding performance. Hereafter, the polyethylene terephthalate will be expressed as PET.

The top plate220may be placed with a small thickness to be able to cover the perforated hole of the bottom plate210. Because a step may occur in the display panel100located above the bottom plate210due to the perforated hole of the bottom plate210, the top plate220may be placed to eliminate such step of the perforated hole.

The back plate230may be disposed on top of the top plate220, and may be provided in a state of being attached to the display panel100instead of being disposed on top of the top plate220with a separate process. A micro-process of a micrometer (μm) unit is used for a manufacturing process of the display panel100. As described above, the plastic substrate, for example, a polyimide (PI)-based substrate, used for the display panel100has flexibility, which is not suitable for the micro-process. Therefore, it is possible to support the display panel by attaching the polyethylene terephthalate that is more rigid to a bottom of the PI-based substrate.

A light-emitting element, a driving circuit for driving the same, and the like may be disposed on the display panel100. Details will be given later.

The polarizing film240may be disposed on top of the display panel100. The polarizing film240may be disposed to solve a malfunction of the light emitting element resulted from an inflow of external light or a decrease in visibility resulted from reflection of the external light.

The cover window250may be disposed on top of the polarizing film240to protect the display apparatus10from an external impact. According to an embodiment of the present disclosure, the cover window250may have a level of flexibility of being able to be folded and rolled via sliding. In general, a cover window250of a glass material may be used a lot. Recently, a continuous development of the cover window250is in progress to be suitable for the foldable display apparatus by allowing a thickness of the cover window250to be extremely small, and using the flexible glass material.

FIG.3is an enlarged view of an area A, which is a portion of a display area DA of the display panel100inFIG.1, and shows a planar shape of sub-pixels arranged in the display area DA.

InFIG.3, a number of anode electrodes151may be arranged in the display area DA, and a bank154may be filled in an area between the anode electrodes151. The bank154may be disposed to cover an edge of the anode electrode151, and may allow only a middle area of the anode electrode151to be in contact with an organic light-emitting stack to define a light-emitting area of the sub-pixel. A spacer155may be disposed in a portion of the area where the bank154is disposed. The spacer155may be disposed to have a constant density in the entire display panel100. The spacer155may serve to support a mask such that the mask for deposition that covers or opens an organic layer for each sub-pixel is not directly in contact with the display panel100during a deposition process for forming the organic light-emitting stack.FIG.3exemplifies a pentile type planar structure in which the sub-pixels are arranged in a dot shape, but the present disclosure may not be limited thereto, and a real type planar structure may also be applied.

FIG.4shows a cross-sectional structure of a sub-pixel taken along a line I-I′ inFIG.3.

Referring toFIG.4, a substrate101, a multi buffer layer102, and a lower buffer layer103may be included, and a first transistor120may be disposed on top of the lower buffer layer103. A first semiconductor layer123constituting the first transistor120, and a lower gate insulating film104for insulation from a first gate electrode122may be disposed on top of the first semiconductor layer123. A first lower interlayer insulating film105and a second lower interlayer insulating film106may be sequentially disposed on top of the first gate electrode122, and an upper buffer layer107may be disposed.

The multi buffer layer102may delay diffusion of moisture or oxygen penetrating into the substrate101, and may be formed as a silicon nitride (SiNx) and a silicon oxide (SiOx) are alternately stacked at least once.

The lower buffer layer103may protect the first semiconductor layer123and may block various types of defects introduced from the substrate. The lower buffer layer103may be made of a-Si, the silicon nitride (SiNx), or the silicon oxide (SiOx).

The first semiconductor layer123of the first transistor120(e.g., a thin-film transistor) may be composed of a polycrystalline semiconductor layer, and the first semiconductor layer123may include a channel area, a source area, and a drain area.

The polycrystalline semiconductor layer has higher mobility than an amorphous semiconductor layer and an oxide semiconductor layer, so that energy consumption is low and reliability is excellent. With such advantage, the polycrystalline semiconductor layer may be used for a driving transistor.

The first gate electrode122may be disposed on top of the lower gate insulating film104, and may be disposed to overlap the first semiconductor layer123.

A second transistor130may be disposed on top of the upper buffer layer107, and a light blocking layer136may be disposed below an area corresponding to the second transistor130. Referring toFIG.4, the light blocking layer136may be disposed on an area corresponding to the second transistor130of the first lower interlayer insulating film105, and a second semiconductor layer133of the second transistor130may be disposed on the second lower interlayer insulating film106and the upper buffer layer107to overlap the light blocking layer136. An upper gate insulating layer137for insulating the second gate electrode132and the second semiconductor layer133from each other may be disposed on the second semiconductor layer133, and then, an upper interlayer insulating film108may be disposed on the second gate electrode132. The first gate electrode122and the second gate electrode132may be composed of a single layer or multiple layers made of one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu) or an alloy thereof, but the present disclosure may not be limited thereto.

The first and second lower interlayer insulating films105and106may be formed as an inorganic film having a higher hydrogen particle content than the upper interlayer insulating film108. For example, the first and second lower interlayer insulating films105and106may be made of the silicon nitride (SiNx) formed by a deposition process using NH3 gas, and the upper interlayer insulating film108may be made of the silicon oxide (SiOx). Hydrogen particles contained in the first and second lower interlayer insulating films105and106may diffuse into the polycrystalline semiconductor layer during a hydrogenation process and fill pores in the polycrystalline semiconductor layer. Accordingly, the polycrystalline semiconductor layer may be stabilized to prevent deterioration of characteristics of the first transistor120. After the activation and hydrogenation processes of the first semiconductor layer123of the first transistor120, the second semiconductor layer133of the second transistor130may be formed. In this regard, the second semiconductor layer133may be formed of an oxide semiconductor. Because the second semiconductor layer133is not exposed to a high-temperature atmosphere of the activation and hydrogenation processes of the first semiconductor layer123, damage to the second semiconductor layer133may be prevented and reliability may be improved. After the upper interlayer insulating film108is disposed, a first source contact hole125S and a first drain contact hole125D may be defined to respectively correspond to source and drain areas of the first transistor, and a second source contact hole135S and a second drain contact hole135dmay be defined to respectively correspond to source and drain areas of the second transistor130. Referring toFIG.4, the first source contact hole125S and the first drain contact hole125D may be defined continuously from the upper interlayer insulating film108to the lower gate insulating film104, and the second source contact hole135S and the second drain contact hole135D may be defined in the second transistor130as well. The first source electrode121and the first drain electrode124corresponding to the first transistor120, and the second source electrode131and the second drain electrode134corresponding to the second transistor130may be formed at the same time. Therefore, the number of processes for forming the source and drain electrodes of each of the first transistor120and the second transistor130may be reduced.

The first source and drain electrodes121and124and the second source and drain electrodes131and134may be composed of a single layer or multiple layers made of one of the molybdenum (Mo), the aluminum (Al), the chromium (Cr), the gold (Au), the titanium (Ti), the nickel (Ni), the neodymium (Nd), and the copper (Cu) or the alloy thereof, but the present disclosure may not be limited thereto. The first source and drain electrodes121and124and the second source and drain electrodes131and134may be of a 3-layer structure. For example, the first source electrode121may be composed of a first layer121a, a second layer121b, and a third layer121c, and other source and drain electrodes may have the same structure.

A storage capacitor140may be disposed between the first transistor120and the second transistor130. As shown inFIG.4, the storage capacitor140may be formed by overlapping a storage lower electrode141and a storage upper electrode142with the first lower interlayer insulating film105interposed therebetween.

The storage lower electrode141may be located on the lower gate insulating film104, and may be formed on the same layer as and made of the same material as the first gate electrode122. The storage upper electrode142may be electrically connected to a pixel circuit via a storage supply line143. The storage upper electrode142may be formed on the same layer as and made of the same material as the light blocking layer136. Such storage upper electrode142may be exposed via a storage contact hole144extending through the second lower interlayer insulating film106, the upper buffer layer107, the upper gate insulating layer137, and the upper interlayer insulating film108to be connected to the storage supply line143. The storage upper electrode142is spaced apart from the light blocking layer136as shown inFIG.4, but is able to be integrally formed with the light blocking layer136. The storage supply line143may be formed on the same plane as and made of the same material as the first source and drain electrodes121and124or the second source and drain electrodes131and134. For this reason, the storage supply line143may be formed simultaneously with the first source and drain electrodes121and124or the second source and drain electrodes131and134through the same mask process.

As an inorganic insulating material such as SiNx or SiOx is deposited on a front face of the substrate101on which the first source and drain electrodes121and124, the second source and drain electrodes131and134, and the storage supply line143are formed, a protective film109may be formed. A first planarization layer110may be formed on the substrate101on which the protective film109is formed. Specifically, the first planarization layer110may be disposed by applying an organic insulating material such as an acrylic-based resin onto a front face of the substrate101on which the protective film109is formed.

After the protective film109and the first planarization layer110are disposed, and a contact hole exposing the first source electrode121or the first drain electrode124of the first transistor120may be defined through a photolithography process. A connection electrode145made of a material of Mo, Ti, Cu, AlNd, Al, and Cr or an alloy thereof may be disposed in a contact hole area exposing the first drain electrode124.

A second planarization layer111may be disposed on the connection electrode145and a contact hole exposing the connection electrode145may be defined in the second planarization layer111, so that the light-emitting element150connected to the first transistor120may be disposed.

The light-emitting element150may include an anode electrode151connected to the first drain electrode124of the first transistor120, at least one organic light-emitting stack152formed on the anode electrode151, and a cathode electrode153formed on the organic light-emitting stack152.

The organic light-emitting stack152may include a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer, and a charge generating layer may be additionally disposed between light-emitting layers in a tandem structure in which a plurality of light-emitting layers are overlapped. The light-emitting layer may emit light of different colors for the sub-pixels. For example, a light-emitting layer for red, a light-emitting layer for green, and a light-emitting layer for blue may be separately formed for the respective sub-pixels. However, a common light-emitting layer may be formed to emit white light without color distinguishment for each pixel, and a color filter that distinguishes the colors may be separately disposed. Such light-emitting layer may be divided into a real RGB Type and a white OLED (WOLED). The light-emitting layers may be individually formed, but the injection layers or the transport layers may be formed as a common layer and may be equally disposed for each sub-pixel.

The anode electrode151may be connected to the connection electrode145exposed through the contact hole extending through the second planarization layer111. The anode electrode151may be formed in a multi-layer structure including a transparent conductive film and an opaque conductive film having a high reflective efficiency. The transparent conductive film is made of a material having a relatively high work function value, such as an indium-tin-oxide (ITO) or an indium-zinc-oxide (IZO), and the opaque conductive film is formed in a single-layer or multi-layer structure containing Al, Ag, Cu, Pb, Mo, Ti, or an alloy thereof. For example, the anode electrode151may be formed in a structure in which the transparent conductive film, the opaque conductive film, and the transparent conductive film are sequentially stacked, or in a structure in which the transparent conductive film and the opaque conductive film are sequentially stacked. Such anode electrode151is disposed on the second planarization layer111so as to overlap not only the light-emitting area defined by the bank154, but also a pixel circuit area where the first and the second transistors120and130and the storage capacitor140are disposed, thereby increasing a light-emitting area.

The organic light-emitting stack152may be formed by stacking the hole transport layer, the organic light-emitting layer, and the electron transport layer on the anode electrode151in order or in a reverse order. In addition, the organic light-emitting stack152may further include the charge generating layer, and may include first and second light-emitting stacks opposite to each other with the charge generating layer interposed therebetween.

The bank154may be formed to expose the anode electrode151. Such bank154may be made of an organic material such as photoacryl, or may be made of a translucent material, but may be made of an opaque material to prevent light interference between the sub-pixels without being limited thereto.

The cathode electrode153may be formed on a top face of the organic light-emitting stack152to be opposite to the anode electrode151with the organic light-emitting stack152interposed therebetween. When the cathode electrode153is applied to a top emission type organic light-emitting display apparatus, the indium-tin-oxide (ITO), the indium-zinc-oxide (IZO), or magnesium-silver (Mg—Ag) may be thinly formed to form the transparent conductive film.

An encapsulation layer170for protecting the light-emitting element150may be formed on the cathode electrode153. The light-emitting element150may react with external moisture or oxygen to cause a dark-spot or a pixel shrinkage due to a nature of the organic light-emitting stack152, so that the encapsulation layer170may be disposed on the cathode electrode153to prevent such phenomenon. The encapsulation layer170may be composed of a first inorganic insulating film171, a foreign material compensation layer172, and a second inorganic insulating film173.

A touch portion may be disposed at an upper portion where the encapsulation layer170is formed. The touch portion may include a first touch planarization layer, a touch electrode, and a second touch planarization layer. The first touch planarization layer and the second touch planarization layer may be disposed to eliminate a step at a point where the touch electrode is disposed and to be electrically well insulated.

FIG.5Ais an enlarged cross-sectional view of an area B that slides in a foldable display apparatus inFIG.1. Referring toFIG.1andFIG.5A, a state in which the display area is reduced and the display panel100is rearwardly rolled into the display apparatus10may be identified. For convenience of description, only the display panel100is expressed, and the plates, the polarizing film240, and the cover window250inFIG.2are omitted.

Referring toFIG.5A, it may be seen that the display panel100extends inwardly along a corner shape of an edge330and has a distal end thereof on an opposite side of the display area.

Referring toFIG.5A, it may be seen that the display panel100has a portion disposed on a first support310and the remaining portion disposed on a bellows400. The bellows400is commonly known as a corrugated tube, and has a characteristic capable of being compressed or tensioned by an external force. Often, the bellows may have a property similar to that of a spring, but, in an embodiment of the present disclosure, the bellows that may be compressed or tensioned to a specific position by the external force and may maintain that state unlike the spring will be preferred. In particular, an embodiment of the present disclosure may target a bellows of an accordion type. The accordion bellows may be given elasticity by being made of a plastic nylon-based brittle material and formed in the corrugated tube shape. Because of the elasticity resulted from the shape of the bellows, the bellows may be compressed as much as desired and expanded as much as desired, and may maintain such compressed and expanded states.

Referring toFIG.5A, it may be seen that one end of the bellows400is coupled to a distal end of the first support310and the other end is coupled to the edge330. The bellows400may be disposed on each of a front face with the display area and a rear face, which is opposite to the front face, to allow the edge330to maintain a coupled state without being twisted or spaced apart from the display apparatus10. Further, the bellows400may simultaneously implement a function to support the display panel100in addition to the function to expand or reduce the display area.

There may be an empty space inside the first support310, and such space may be referred to as a first accommodation portion340. In the first accommodation portion340, a battery, a circuit driver, and the like, which are components necessary for the display panel100to be driven, may be disposed. Further, there may be an empty space between the two bellows400opposite to each other, and such space may be referred to as a second accommodation portion350. The second accommodation portion350may also provide an additional space for disposing components necessary for the display panel100to be driven in connection with the first accommodation portion340.

FIG.5Bis a cross-sectional view showing a state in which the display area is expanded from the state inFIG.5Ain which the display area is reduced in the display apparatus10according to an embodiment of the present disclosure. Referring further toFIG.5B, it may be seen that the bellows400is expanded and unfolded compared to that inFIG.5A, and the display panel100is disposed as far as possible to the front with respect to the edge330, and thus, the display area is expanded.

Referring toFIG.5B, it may be seen that the area between the two opposite bellows400is expanded compared to that inFIG.5A, and thus, the second accommodation portion350is expanded.

FIG.6is an enlarged cross-sectional view of an area C inFIG.5A. Referring toFIG.6, all of the upper and lower layers of the display panel100omitted inFIGS.5A and5Bare shown. There is the bottom plate210in direct contact with the bellows400. The top plate220, the back plate230, the display panel100, the polarizing film240, and the cover window250may be sequentially disposed on the bottom plate210. It may be seen that the above-described display panel100and adjacent layers thereof extend inwardly of the edge330along a semicircular corner of the edge330to a non-display area, which is on an opposite side.

The bottom plate210may be made of a hard PET material, so that the bottom plate210may be in direct contact with the bellows400and may protect the display panel100while having durability against the movement of contraction and expansion of the bellows400. Further, the bottom plate210may have a great thickness and may have the perforated holes (not shown) defined throughout the bottom plate210such that the display panel100of the display apparatus10may be folded or rolled while enduring the contraction and expansion movement of the bellows400.

Referring toFIG.6, it may be identified that a bellows guide bar410in a form of a bar is disposed in a portion of the bellows400. The bellows guide bar410may serve to guide the bellows400to have uniformity in an x direction when contracting and expanding to reduce and expand the display area of the display apparatus10.

Referring toFIG.7, the display panel100and the upper and lower layers are omitted, and the first support310, the edge330, the bellows400, and the bellows guide bar410are arranged. It may be seen from the perspective view that a panel through-hole360that allows the display panel100, the upper and lower layers thereof, and the cover window250to enter through a side face of the edge330is defined. The panel through-hole360is defined in upper and lower portions of the side face of the edge330, so that, when the display area is reduced and expanded, the display panel100and the upper and lower layers thereof may move smoothly.

In addition, there is the second support320placed between the first support310and the edge330, and an LM (linear motor) guide420may be attached to the second support320.

A guide fastening portion430and the bellows guide bar410may be disposed on the LM guide420. The LM guide420may include a linear motor, and the guide fastening portion430may move with respect to the LM guide420in response to operation of the linear motor.

Specifically, when the guide fastening portion430moves along a driving shaft of the LM guide420, the bellows guide bar410connected to the guide fastening portion430may move along the driving shaft of the LM guide420.

Referring toFIG.7, the guide fastening portion430may be driven in the x-axis direction, and the LM guide420may be disposed parallel to the x-axis direction.

The bellows guide bar410may be disposed parallel to a z-axis, and the bellows guide bar410is uniformly disposed to guide the bellows400to constantly move for each zone during the contraction/expansion in the x-axis direction. Because of the characteristics of the bellows400, a portion that is folded and unfolded during the contraction and the expansion may vary locally. Due to such phenomenon, when there is no LM guide420, the bellows guide bar410, and the guide fastening portion430, there may be a difference in movement positions of the second support320and the edge330on left and right sides.

FIG.8is a plan view showing the structure inFIG.7according to an embodiment of the present disclosure in a plane. Referring toFIG.8, the components like the first support310, the second support320, the edge330, and the bellows400from which the display panel100and the upper and lower layers inFIG.7are omitted may be seen, and it may be seen that the bellows guide bar410is disposed inside the bellows400.

An outer portion of the second support320may be moved to be covered by the first support310or placed into the first support310. As one end of the bellows400is fixed to the first support310and the other end of the bellows400is fixed to the edge330, the edge330may repeat moving closer to and further from the first support310.

Referring toFIG.8, the bellows guide bar410may be disposed inside the bellows400, and a portion of the bellows guide bar410may be disposed below the first support310in a situation in which the bellows400is not fully unfolded.

As in the description inFIG.7, the LM guide420may be placed on an inner face of the second support320, and the LM guide420and the guide fastening portion430are coupled to each other for the driving. The guide fastening portion430and the bellows guide bar410may be coupled to each other, so that the bellows guide bar410may be constantly driven in the x-axis direction, which is the disposition direction of the LM guide420. When the bellows400expands from the contracted state, the bellows guide bar410disposed in the bellows400is pushed out together.

FIGS.9A and9Bshow a deformable usage scheme of the foldable display apparatus10according to an embodiment of the present disclosure.FIG.9Amay fold all of the bellows400to allow the display panel100to be minimally exposed to minimize the display area.FIG.9Bshows a scheme of folding the foldable display apparatus10inFIG.9Baccording to an embodiment of the present disclosure with respect to a hinge370at a center at an angle of about 90 degrees. Because the foldable display apparatus10has a small size, such form is suitable for a mobile environment. In particular, in the case ofFIG.9B, there is an advantage in which the display apparatus is stably gripped while identifying an image of a camera installed on the back face in real time because of the folding around the hinge370.

FIGS.10A and10Bshow a method of utilizing the foldable display apparatus10in a state in which a screen size thereof is increased by the expansion of the bellows400. As the bellows400is expanded, the display panel100may be exposed as much as possible, which may be suitable for use with a wide screen with a desk or a mounting space rather than the mobile environment to fit the increased screen size. Referring toFIG.10B, the foldable display apparatus10may be folded around the hinge370and may be used in a laptop form.

The display apparatus according to an embodiment of the present disclosure may have the flexibility and the spring-like elasticity at the same time when expanding and contracting with only a geometric structure by applying the accordion type bellows. Therefore, it is possible to implement a slidable display apparatus for the enlargement and the reduction of the display screen with minimal use of space without a need for a separate dynamic driver.

The display according to an embodiment of the present disclosure may include a liquid crystal display apparatus (LCD), a field emission display apparatus (FED), an organic light-emitting display apparatus (OLED), and a quantum dot display apparatus.

The display according to an embodiment of the present disclosure may also include the set electronic apparatus or the set apparatus such as the laptop computer, the television, and the computer monitor, the equipment display including the automotive display or the displays of other types of the vehicle, the mobile electronic apparatus such as the smartphone or the electronic pad, and the like, which are the complete products (or the final products) including the LCM, the OLED module, and the like.

A display apparatus according to an embodiment of the present disclosure may be described as follows.

A first aspect of the present disclosure provides a foldable display apparatus comprising: a display panel having a light-emitting element disposed thereon; a cover window disposed on top of the display panel; a bottom plate disposed beneath the display panel; a bellows for supporting at least a portion of the bottom plate; a first support coupled with one end of the bellows; and an edge coupled with the other end of the bellows.

In one implementation of the first aspect, the foldable display apparatus further includes: a second support disposed between the first support and the edge.

In one implementation of the first aspect, the foldable display apparatus further includes: an LM guide disposed inwardly of the second support; and a guide fastening portion movable with respect to the LM guide.

In one implementation of the first aspect, the foldable display apparatus further includes: a bellows guide bar disposed inside the bellows and coupled to the guide fastening portion.

In one implementation of the first aspect, the foldable display apparatus further includes: a first accommodation portion defined beneath the first support and a second accommodation portion defined beneath the bellows; and a driver of the light-emitting element disposed in at least one of the first accommodation portion and the second accommodation portion.

In one implementation of the first aspect, a panel through-hole for sliding the display panel, the cover window, and the bottom plate is defined in one face of the edge.

In one implementation of the first aspect, the panel through-hole is defined in each of at least two faces of the edge.

In one implementation of the first aspect, a hinge is disposed on the other face of the display apparatus where the first support and the bellows are coupled to each other.

A second aspect of the present disclosure provides a foldable display apparatus including a bottom plate, a display panel, and a cover window sequentially disposed, the foldable display apparatus comprising: a bellows for supporting at least a portion of the bottom plate; a first support for supporting another portion of the bottom plate; and an edge disposed at one end of the bottom plate.

In one implementation of the second aspect, a panel through-hole for sliding the display panel, the cover window, and the bottom plate is defined in one face of the edge.

In one implementation of the second aspect, the panel through-hole is defined in each of at least two faces of the edge.

In one implementation of the second aspect, the foldable display apparatus further includes: a second support disposed between the first support and the edge.

In one implementation of the second aspect, the foldable display apparatus further includes: an LM guide disposed inwardly of the second support; and a guide fastening portion movable with respect to the LM guide.

In one implementation of the second aspect, the foldable display apparatus further includes: a bellows guide bar disposed inside the bellows and coupled to the guide fastening portion.

In one implementation of the second aspect, the foldable display apparatus further includes: a first accommodation portion defined beneath the first support and a second accommodation portion defined beneath the bellows; and a driver of a light-emitting element disposed in at least one of the first accommodation portion and the second accommodation portion.

Features, structures, effects, and the like described in the examples of the present application described above are included in at least one example of the present application, and are not necessarily limited to only one example. Furthermore, features, structures, effects, and the like illustrated in at least one example of the present application may be combined or modified with respect to other examples by those of ordinary skill in the art to which the present application belongs. Accordingly, the contents related to such combinations and modifications should be interpreted as being included in the scope of the present application.

The present disclosure as described above is not limited to the above-described embodiments and the accompanying drawings. It will be apparent to those of ordinary skill in the technical field to which the present disclosure belongs that various substitutions, modifications and changes may be made within the scope not departing from the technical ideas of the present disclosure. Therefore, the scope of the present disclosure is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present disclosure.