FLEXIBLE DISPLAY AND ELECTRONIC DEVICE INCLUDING THE SAME

A flexible display is provided. The flexible display includes a display panel and a transparent member disposed on the display panel. The transparent member may a first glass portion having a first thickness, and a second glass portion having a second thickness thinner than the first thickness. An upper surface of the second glass portion is recessed in a direction toward the display panel with respect to an upper surface of the first glass portion. A lower surface of the second glass portion is recessed in an opposite direction to the display panel with respect to a lower surface of the first glass portion.

BACKGROUND

The disclosure relates to a bendable flexible display and an electronic device including the same.

2. Description of Related Art

Recently, there is increasing interest in bendable electronic devices (also referred to as ‘flexible electronic devices’) including a bendable flexible display (simply ‘flexible display’). The window member used in the flexible display requires flexibility in order to prevent deformation when folded or bent as well as impact resistance from surface hardness or strength.

SUMMARY

Aspects of the disclosure are to address at least the above-mentioned problems and/or disadvantages and to provide at least the advantages described below. Accordingly, an aspect of the disclosure is to provide a transparent member with enhanced flexibility and strength and a flexible display including the same.

In accordance with an aspect of the disclosure, a flexible display is provided. The flexible display includes a display panel and a transparent member disposed on the display panel. The transparent member may a first glass portion having a first thickness, and a second glass portion having a second thickness thinner than the first thickness. An upper surface of the second glass portion is recessed in a direction toward the display panel with respect to an upper surface of the first glass portion. A lower surface of the second glass portion is recessed in an opposite direction to the display panel with respect to a lower surface of the first glass portion.

In accordance with another aspect of the disclosure, an electronic device is provided. The electronic device includes a housing including a first housing and a second housing, a hinge module connected with the first housing and the second housing, and a flexible display at least partially received in the first housing and the second housing. The flexible display includes a display panel and a transparent member disposed on the display panel. The transparent member may a first glass portion having a first thickness, and a second glass portion having a second thickness thinner than the first thickness. An upper surface of the second glass portion is recessed in a direction toward the display panel with respect to an upper surface of the first glass portion. A lower surface of the second glass portion is recessed in an opposite direction to the display panel with respect to a lower surface of the first glass portion.

In accordance with another aspect of the disclosure, a flexible transparent member is provided. The flexible transparent member includes a second glass portion having a second thickness thinner than the first thickness and a resin portion disposed on the second glass portion. An upper surface of the second glass portion is recessed in a downward direction with respect to an upper surface of the first glass portion. A lower surface of the second glass portion is recessed in an upward direction with respect to a lower surface of the first glass portion. The resin portion is filled in the recessed region.

According to various embodiments of the disclosure, it is possible to evenly disperse internal stress by etching the upper side and the lower side of a thin portion of the transparent member with different thicknesses.

According to various embodiments of the disclosure, it is possible to prevent warpage by forming a chemically reinforced area to have different reinforcement depths in a thick portion and a thin portion in a transparent member with different thicknesses.

DETAILED DESCRIPTION

Referring toFIG.1, an electronic device101in a network environment100may communicate with a first external electronic device102via a first network198(e.g., a short-range wireless communication network), a second external electronic device104, or a server108via a second network199(e.g., a long-range wireless communication network). According to an embodiment of the disclosure, the electronic device101may communicate with the second external electronic device104via the server108. According to an embodiment of the disclosure, the electronic device101may include a processor120, a memory130, an input module150, a sound output module155, a display module160, an audio module170, a sensor module176, an interface177, a connecting terminal178, a haptic module179, a camera module180, a power management module188, a battery189, a communication module190, a subscriber identification module (SIM)196, and an antenna module197. In an embodiment of the disclosure, at least one (e.g., the connecting terminal178) of the components may be omitted from the electronic device101, or one or more other components may be added in the electronic device101. According to an embodiment of the disclosure, some (e.g., the sensor module176, the camera module180, or the antenna module197) of the components may be integrated into a single component (e.g., the display module160).

The processor120may execute, for example, a software (e.g., a program140) to control at least one other component (e.g., a hardware or software component) of the electronic device101coupled with the processor120, and may perform various data processing or computation. According to an embodiment of the disclosure, as at least part of the data processing or computation, the processor120may store a command or data received from another component (e.g., the sensor module176or the communication module190) in a volatile memory132, process the command or the data stored in the volatile memory132, and store resulting data in a non-volatile memory134. According to an embodiment of the disclosure, the processor120may include a main processor121(e.g., a central processing unit (CPU) or an application processor (AP)), or an auxiliary processor123(e.g., a graphics processing unit (GPU), a neural processing unit (NPU), an image signal processor (ISP), a sensor hub processor, or a communication processor (CP)) that is operable independently from, or in conjunction with, the main processor121. For example, when the electronic device101includes the main processor121and the auxiliary processor123, the auxiliary processor123may be configured to use less power than the main processor121or designated to perform a specific function. The auxiliary processor123may be implemented as separate from, or as part of the main processor121.

The camera module180may capture a still image or moving images. According to an embodiment of the disclosure, the camera module180may include one or more lenses, image sensors, ISPs, or flashes.

The power management module188may manage power supplied to the electronic device101. According to an embodiment of the disclosure, the power management module188may be implemented as at least part of, for example, a power management integrated circuit (PMIC).

FIG.2Ais a perspective view illustrating an electronic device in an unfolding state according to an embodiment of the disclosure.FIG.2Bis a perspective view of an electronic device in a folding state according to an embodiment of the disclosure.FIG.3is an exploded view illustrating an electronic device according to an embodiment of the disclosure. The electronic device shown inFIGS.2A,2B, and3is for illustrative purposes only, and the disclosure is not limited by the drawings. The XYZ coordinate system shown inFIGS.2A,2B, and3is for illustrative purposes of describing the layout of the components and does not limit the scope of the claims.

Referring toFIGS.2A,2B, and3, an electronic device200(e.g., the electronic device101ofFIG.1) may include at least one pair of housings210and220. The pair of housings210and220may be rotatably coupled to fold about, e.g., a hinge (e.g., a hinge240ofFIG.3) while facing each other. For example, the pair of housings210and220may include a first housing210and a second housing220. The first housing210and the second housing220may be disposed on two opposite sides of the folding axis F. One end area of the first housing210and one end area of the second housing220may be disposed side by side with the hinge240interposed therebetween. The first housing210and the second housing220may have symmetrical shapes with respect to a plane including the folding axis F and extending in the Z1-axis direction. Here, the folding axis F may be an axis in the X1 direction, formed by the hinge240.

The first housing210may have substantially the same length as the second housing220(e.g., length in the Y1-axis direction), but is not limited thereto. The first housing210may have substantially the same width as the second housing220(e.g., width in the X1-axis direction), but is not limited thereto.

Hereinafter, ‘unfolding state (or flat state)’ or ‘unfolded state’ may refer to a state in which the angle between the first housing210and the second housing220is substantially 180 degrees. ‘Folding state’ or a ‘folded state’ may refer to a state in which the angle formed between the first housing210and the second housing220is substantially 0 degrees. ‘Intermediate state’ may refer to any state between the unfolding state and the folding state. The electronic device200may rotate about the hinge240such that the first housing210and the second housing220form an angle from 0 degrees to 180 degrees, for example. The electronic device200may rotate about the hinge240such that the first housing210and the second housing220form an angle from 180 degrees to 360 degrees, for example.

The first housing210may include a first surface210aand a second surface210b. For example, the first surface210amay be provided to face in a first direction (e.g., +Z1-axis direction). The first surface210amay be, e.g., a surface on which at least a portion of a flexible display230is disposed. The first surface210amay refer to, e.g., a virtual surface overlapping at least a portion of the flexible display230. For example, the second surface210bmay be provided to face in a second direction (e.g., −Z1-axis direction). The second surface210bmay be, e.g., a surface on which a first rear cover212is disposed. The second surface210bmay be parallel to the first surface210a. The second surface210bmay refer to a plane defined by, e.g., the first rear cover212.

The second housing220may include a third surface220aand a fourth surface220b. For example, the third surface220amay be provided to face in the first direction (e.g., +Z1-axis direction). The third surface220amay be, e.g., a surface on which at least a portion of the flexible display230is disposed. The third surface220amay refer to, e.g., a virtual surface overlapping at least a portion of the flexible display230. For example, the fourth surface220bmay be provided to face in a second direction (e.g., −Z1-axis direction). The fourth surface220bmay be, e.g., a surface on which a second rear cover222is disposed. The fourth surface220bmay be parallel to the third surface220a. The fourth surface220bmay refer to a plane defined by, e.g., the second rear cover222.

When the electronic device200is unfolded, the first surface210aand the third surface220amay be positioned within one arbitrary virtual plane (e.g., an x-y plane). For example, the first surface210aand the third surface220amay form the same plane when the electronic device200is unfolded. For example, the first surface210aand the third surface220amay be disposed to form 180 degrees with respect to the x-y plane in the unfolding state. When the electronic device200is unfolded, the second surface210band the fourth surface220bmay be positioned within another arbitrary virtual plane (e.g., an x-y plane). For example, the second surface210band the fourth surface220bmay form the same plane in the unfolding state of the electronic device200. For example, the second surface210aand the fourth surface220bmay be disposed to form 180 degrees with respect to the x-y plane in the unfolding state.

In the folding state of the electronic device200, at least a portion of the first surface210aand at least a portion of the third surface220amay face each other. For example, in the folding state of the electronic device200, the angle between the first surface210aand the third surface220amay be 0 degrees from the x-y plane. As the electronic device200is folded from the unfolding state, the angle between the first surface210aand the third surface220afrom the x-y plane may gradually decrease. For example, the angle formed between the first surface210aand the third surfaces220afrom the x-y plane in the intermediate state may be determined between about 0 degrees and about 180 degrees. In the folding state of the electronic device200, the second surface210band the fourth surface220bmay be parallel to each other. For example, the second surface210band the fourth surface220bmay face in opposite directions in the folding state of the electronic device200.

The pair of housings210and220included in the electronic device200is not limited to the shape and coupling shown but may rather be implemented in other shapes or via a combination and/or coupling of other components.

The first housing210may include a first side frame211. The first side frame211may constitute a side surface of the first housing210. The first side frame211may form part of the exterior of the first housing210. The first side frame211may be provided to protect components received inside the electronic device200from the outside.

The first side frame211may include a first side member211a, a second side member211b, and/or a third side member211c. The first side member211amay have a first length along a first length direction (e.g., Y1-axis direction). The second side member211bmay extend from the first side member211ain a substantially vertical direction (e.g., the X1-axis direction). The second side member211bmay extend to have a second length equal to or different from the first length. The third side member211cmay extend from the second side member211bin a substantially vertical direction (e.g., the Y1-axis direction). The third side member211cmay extend in a direction substantially parallel to the first side member211a. The third side member211cmay have a first length along the first length direction (e.g., Y1-axis direction).

The first side member211a, the second side member211b, and the third side member211cmay be disposed to be visible from the outside. At least a portion of the first side member211a, the second side member211b, and/or the third side member211cmay be formed of a curved surface. The first side frame211may be formed in a quadrilateral shape (e.g., square or rectangle) by the first side member211a, the second side member211b, and the third side member211c. The first side member211a, the second side member211b, and the third side member211cmay be integrally formed but are not limited thereto.

The second housing220may include a second side frame221. The second side frame221may constitute a side surface of the second housing220. The second side frame221may form part of the exterior of the second housing220. The second side frame221may be provided to protect components received inside the electronic device200from the outside.

The second side frame221may include a fourth side member221a, a fifth side member221b, and/or a sixth side member221c. The fourth side member221amay have a third length along a first length direction (e.g., Y1-axis direction). The fifth side member221bmay extend from the fourth side member221ain a substantially vertical direction (e.g., the X1-axis direction). The fifth side member221bmay extend to have a fourth length equal to or different from the third length. The sixth side member221cmay extend from the fifth side member221bin a substantially vertical direction (e.g., the Y1-axis direction). The sixth side member221cmay extend in a direction substantially parallel to the fourth side member221a. The sixth side member221cmay have a third length along the first length direction (e.g., Y1-axis direction).

The fourth side member221a, the fifth side member221b, and the sixth side member221cmay be disposed to be visible from the outside. At least a portion of the fourth side member221a, the fifth side member221b, and/or the sixth side member221cmay be formed of a curved surface. The second side frame221may be formed in a quadrilateral shape (e.g., square or rectangle) by the fourth side member221a, the fifth side member221b, and the sixth side member221c. The first length may be substantially equal to the third length. The second length may be substantially equal to the fourth length. The fourth side member221a, the fifth side member221b, and the sixth side member221cmay be integrally formed but are not limited thereto.

In the unfolding state of the electronic device200, the first side member211aand the fourth side member221amay be positioned substantially in a straight line. In the unfolding state of the electronic device200, the second side member211band the fifth side member221bmay be parallel to each other. In the unfolding state of the electronic device200, the third side member211cand the sixth side member221cmay be positioned substantially in a straight line.

In the folding state of the electronic device200, the first side member211aand the fourth side member221amay overlap each other. In the folding state of the electronic device200, the second side member211band the fifth side member221bmay overlap each other. In the folding state of the electronic device200, the third side member211cand the sixth side member221cmay overlap each other.

The first housing210may include a first rear cover212. The first rear cover212may form at least a portion of the second surface210bof the first housing210. The first rear cover212may be combined with the first side frame211. The first rear cover212may be integrally formed with, e.g., the first side frame211.

The second housing220may include a second rear cover222. The second rear cover222may form at least a portion of the fourth surface220bof the second housing220. The second rear cover222may be combined with the second side frame221. The second rear cover222may be integrally formed with, e.g., the second side frame221.

The first rear cover212and/or the second rear cover222may be formed of at least one of, or a combination of at least two of, laminated or colored glass, ceramic, Glastic, polymer, or metal (e.g., aluminum, stainless steel (STS), or magnesium).

The electronic device200may include a flexible display230(e.g., a foldable display or display). The flexible display230may be disposed across the first housing210, the hinge240, and the second housing220. The flexible display230may be disposed from the first surface210aof the first housing210across the hinge structure240up to at least a portion of the third surface220aof the second housing220. The flexible display230may be disposed so that the first surface210aof the first housing210and the third surface220aof the second housing220overlap. A portion of the flexible display230corresponding to the hinge240may be bent according to the rotation of the hinge240.

In the unfolding state, the flexible display230may be disposed to be visible from the outside. In a folding state, the flexible display230may be disposed to be invisible from the outside.

The electronic device200may include a protective cover231. The protective cover231may be positioned to protect an edge portion of the flexible display230. The protective cover231may form part of the exterior of the electronic device200.

The electronic device210may include at least one of an input device (e.g., a microphone203), a sound output device (e.g., a receiver201for phone calls or speaker202), sensor modules204, the camera module (a first camera module205or a second camera module208), a connector port207, a key input device (not shown), or an indicator (not shown), disposed in a first inner space214of the first housing210or a second inner space224of the second housing220. The electronic device200may be configured to omit at least one of the above-described components or add other components.

The input device may include a plurality of microphones disposed to detect the direction of sound. The sound output device may include, e.g., the receiver201for phone calls and the speaker202. The sound output devices201and202may be disposed to face the outside through at least one speaker hole, formed in the first housing210or the second housing220. The connector port207may be disposed to face the outside through a connector port hole, formed in the first housing210or the second housing220.

The sensor module204may produce an electrical signal or data value corresponding to the internal operation state or external environment state of the electronic device200. The sensor module204may include at least one of a proximity sensor, an illuminance sensor, a time of flight (TOF) sensor, an ultrasonic sensor, a fingerprint recognition sensor, a gesture sensor, a gyro sensor, an air pressure sensor, a magnetic sensor, an accelerometer, a grip sensor, a color sensor, an IR sensor, a biometric sensor, a temperature sensor, or a humidity sensor.

The camera module may include the first camera module205disposed on the front (e.g., surface in the +Z1-axis direction) of the electronic device200or a second camera module208disposed on the rear surface (e.g., surface in the −Z1-axis direction) of the electronic device200. The first camera module205and/or the second camera module208may include one or more lenses, an image sensor, and/or an ISP. For example, the first camera module205may be disposed under the flexible display230and be configured to capture a subject through a portion of the active area of the flexible display230. The flash209may be disposed on the second camera module208. The flash209may include, e.g., a light emitting diode (LED) or a xenon lamp.

FIG.4Ais a plan view illustrating a flexible display according to an embodiment of the disclosure.FIG.4Bis an exploded perspective view of a flexible display according to an embodiment of the disclosure;

Referring toFIG.4AandFIG.4B, the flexible display230may include a first area230aand a second area230bextending from the first area230a. The first area230amay refer to a flat area that maintains a flat surface even when the electronic device (e.g., the electronic device200ofFIG.2A) is folded about the folding axis F. Alternatively, the first area230amay refer to an area that is not deformed when the electronic device200is folded about the folding axis F. Alternatively, the first area230amay refer to a non-flexible area. The second area230bmay refer to a bending area or a flexible area that is bent when the electronic device200is folded about the folding axis F. Alternatively, the second area230bmay refer to a deformable area when the electronic device200is folded around the folding axis F. The second area230bmay be positioned between two first areas230a. The second area230bmay be formed to be symmetrical with respect to, e.g., the folding axis F, but is not limited thereto. The second area230bmay refer to, e.g., an area having a predetermined length with respect to the folding axis F.

The flexible display230may include a display panel and a transparent member (e.g., the transparent member ofFIGS.7A to10,11A,11B,11C, and12). Like the flexible display230, the display panel may include a flexible area (e.g., the second area230b)(or deformable area) and a non-flexible area (e.g., the first area230a) adjacent to the flexible area.

The display panel may be provided to display an image. The display panel may be, e.g., a light emitting display panel, but is not limited thereto. The display panel may be, e.g., an organic light emitting display panel or a quantum dot light emitting display panel. The light emitting layer of the organic light emitting display panel may include an organic light emitting material. The light emitting layer of the quantum dot light emitting display panel may include quantum dots and quantum rods. The display panel may be flexible.

The transparent member300(or window) may be disposed on, e.g., the display panel. Different components (e.g., input detection units) may be disposed between the transparent member300and the display panel. The transparent member300may include an optically transparent insulating material. Accordingly, the image generated by the display panel may be easily transferred to the user through the transparent member300.

The transparent member300may transmit the image from the display panel while mitigating the external impact, thereby preventing the display panel from being damaged or malfunctioning due to the external impact. Here, the external impact is a force applied from the outside, such as pressure and stress, and may refer to a force that causes damage to the display panel.

Referring toFIG.4B, the flexible display230may include a protective member232(e.g., a protective film), a transparent member233, and a display panel234. According to one embodiment, the flexible display230may be configured to sequentially stack the protective member232, the transparent member233, and the display panel234from the top. Each component may be adhered by adhesive members P1and P2, but is not limited thereto.

The adhesive members P1and P2may include at least one of an optically clear adhesive film (OCA), an optically clear adhesive resin (OCR), a pressure sensitive adhesive film (PSA), and heat reactive adhesive, a general adhesive, or a double-sided tape. The adhesive members P1and P2may include a photocuring adhesive material or a heat curing adhesive material, and the material is not particularly limited. The adhesive members P1and P2may include, for example, a first adhesive member P1provided to adhere the protective member232and the transparent member233, and a second adhesive member P2provided to adhere the transparent member233and the display panel234.

The first adhesive member P1may be disposed to be attached to at least a portion of the upper surface of the transparent member233. The second adhesive member P2may be disposed to be attached to at least a portion of the lower surface of the transparent member233. However, it is not limited thereto, and as will be described later, the first adhesive member P1may be attached to a portion of the upper surface of the transparent member233, and the second adhesive member P2may be attached to the remaining portion of the upper surface of the transparent member233. Adhesive members with different physical properties may be provided around the transparent member233in various ways and structures.

The configuration shown inFIG.4Bis an example for convenience of explanation, and the flexible display230may further include additional configurations. For example, although not shown, various types of layers, such as a touch sensing layer, may be provided on the upper side of the display panel234. The touch sensing layer may be configured to obtain the coordinate accuracy of an external input. The touch sensing layer may be, for example, a capacitive touch-sensitive member. However, it is not limited thereto and may be replaced with another type of touch sensing layer including two types of touch electrodes, such as an electromagnetic induction type.

According to one embodiment, the display panel234may be disposed below the transparent member233. For example, the display panel234may be disposed below the transparent member233with a polarizing layer235interposed therebetween. The display panel234may be a display panel such as an organic light emitting display panel, an electrophoretic display panel, an electrowetting display panel, or a quantum dot display panel, but the type is not limited. A light emitting layer of the organic light emitting display panel may include an organic light emitting material. A light emitting layer of the quantum dot display panel may include quantum dots and quantum rods. At least a portion of the display panel234may be bendable. For example, the display panel234may be formed so that at least a portion of the display panel234is deformable.

According to one embodiment, the flexible display230may include a polarization layer235. The polarization layer235may be disposed on the display panel234. For example, the polarizing layer235may be disposed between the transparent member233and the display panel234. The polarization layer235may reduce the external light reflectance of the flexible display230by absorbing or destructively interfering with light incident from the outside. For example, the polarizing layer235may be formed integrally with the display panel234through a continuous process. For example, the polarization layer235may be a component of the display panel234. In case that the polarizing layer235and the display panel234are formed integrally, the adhesive member between them can be omitted. In case that the polarizing layer235is manufactured separately and attached to the display panel234, the polarizing layer235and the display panel may be attached by an adhesive member.

According to one embodiment, the transparent member233may be disposed on the display panel234. The transparent member233may be attached to the display panel234by using an adhesive member to directly contact the display panel234. However, it is not limited thereto, and various types of layers, such as the polarizing layer235or the touch sensing layer (not shown), may be provided between the transparent member233and the display panel234.

According to one embodiment, the surface of the transparent member233may be chemically strengthened to supplement rigidity. A detailed description of the transparent member233will be provided later.

According to one embodiment, the protective member232(e.g., protective film) may be disposed on the top layer of the flexible display230. The protective member232may be disposed on the upper side of the transparent member233to protect the transparent member233from external impact. The protective member232may protect the transparent member233from external shock and may help prevent glass pieces from scattering when the transparent member233is damaged.

The protective member232and the transparent member233may be adhered by the first adhesive member P1. As the protective member232and the transparent member233are adhered to each other, the first adhesive member P1may be disposed between the protective member232and the transparent member233.

According to one embodiment, the protective member232may be attached to the transparent member233to be detachable. In case that the protective member232is damaged due to an external impact, a new protective member232may be attached on the transparent member233. Therefore, an adhesive force of the first adhesive member P1may be weaker than an adhesive force of the second adhesive member P2.

According to one embodiment, the protective member232may include polyethylene terephthalate (PET) or polyimide (PI), but is not limited thereto, and may include a material used for the transparent member233or the polymer member236to be described later. For example, a thickness of the protective member232may be substantially the same as a thickness of the transparent member233or may be relatively thinner. As an example, the protective member232may be omitted from the configuration of the flexible display230. If the protection member232is omitted, the first adhesive member P1may also be omitted.

According to one embodiment, the flexible display230may include a polymer member236disposed below the display panel234. For example, the polymer member236may have a dark color applied to help display a background when the display is off. For example, the polymer member236may serve as a buffering member to prevent or reduce damage to the flexible display230by absorbing shock from the outside of the electronic device.

Although not shown, a metal sheet layer may be disposed below the display panel234. The metal sheet layer may help reinforce the rigidity of electronic devices. The metal sheet layer may be used, for example, to shield ambient noise and dissipate heat radiating from surrounding heat dissipating components. The metal sheet layer may include at least one of STS, Cu, Al, or other alloy materials.

FIG.5is a flowchart illustrating a manufacturing process of a transparent member included in a flexible display ofFIG.4Aaccording to an embodiment of the disclosure.

Referring toFIG.5, a transparent member (e.g., the transparent member300ofFIG.7A) according to an embodiment may be manufactured through a base glass cutting process (S10), a first chemical-reinforcing of the cut glass process (S20), a masking a portion of the first chemical-reinforced glass and then performing shape etching process (S30), demasking after etching process (S40), a second chemical-reinforcing the surface of the masked glass process (S50), or cleaning the surface to remove foreign substances process (S60).

According to an example, in process S10, a process of cutting the base glass to the size of a flexible display (e.g., the flexible display230ofFIG.4) may be performed. In process S10, a process of cutting the base glass to a predetermined size may be performed.

According to an example, in process S20, a process of first chemical-reinforcing the surface of the cut glass may be performed. The first chemical-reinforcing process may proceed for a first period. Here, a depth of reinforcing by the first chemical-reinforcing process may vary depending on the length of the first period. The longer the first period, the more areas can be chemically reinforced through the first chemical-reinforcing process.

Here, chemical reinforcement may be performed by ion substitution. Here, the ion substitution may refer to a method of exchanging small-sized ions present in the glass with large-sized ions.

As an example of the ion substitution, as Na+ions (sodium ions) inside the glass are substituted with K+ions (potassium ions), internal stress may be generated, reinforcing the strength of the glass. If K+ions penetrate into the glass through chemical reinforcement, Na+ions in the glass may be discharged to the outside, so that ion substitution may be performed.

As an example of the ion substitution, a two-step substitution process in which Li+ions (lithium ions) in the glass are first substituted with Na+ions, and then the Na+ions are substituted with K+ions is performed, thereby generating internal stress to reinforce the strength of the glass.

The ion substitution is not limited to the above method, and may be performed in various ways in which ions in the glass (especially the surface of the glass) are substituted with relatively large ions.

According to an example, in process S20, a KNO3(potassium nitrate) solution may be used to chemically reinforce the glass, but is not limited thereto. For example, a potassium hydroxide (KOH) solution may be used for chemical reinforcement. For example, chemical reinforcement may be performed by immersing glass in a chemical solution containing KNO3.

Chemical reinforcement may be performed in a temperature environment of, e.g., 300° C. to 400° C., but is not limited thereto, and may vary depending on the material of the glass used. Chemical reinforcement may be sequentially performed from the surface layer of the glass. The chemical reinforcement depth at which the chemical reinforcement is performed may be proportional to the temperature and the reinforcement time. In process S20, the chemical reinforcement depth of the glass may be adjusted by adjusting the temperature and reinforcement time.

According to an example, in process S30, a process of performing shape etching after masking a portion of the surface of the glass that has undergone first chemical reinforcement may be performed. Before the shape etching, a masking member may be attached to a portion that is not to be etched. For example, masking may be performed on the portion corresponding to the non-flexible area or the first area (e.g., the first area230aofFIG.4A) of the flexible display230. Shape etching may be performed after masking is completed. The thickness of the unmasked portion may decrease due to shape etching. The thinned portion may be a portion corresponding to the second area (e.g., the second area230bofFIG.4A) of the flexible display230. Etching may be performed by a laser irradiation method, for example.

According to an embodiment of the disclosure, in the shape etching process, not only the upper surface but also the lower surface may be etched in the unmasked portion of the glass. Therefore, notches or recesses may be formed in the upper and lower surfaces of the glass. By forming notches or recesses in the upper and lower sides of the glass, stress may be evenly dispersed. If the stress is evenly dispersed, the glass may be prevented from being twisted by the stress.

According to an example, in process S40, after the shape etching is completed, the masking member attached to the glass surface may be removed. As a component, such as a separate jig, rather than the masking member, is used, the process of removing the masking member may be omitted.

According to an example, in process S50, a process of second chemical-reinforcing the surface of the demasked glass may be performed. The etched portion of the glass may be in a state in which the area first chemically reinforced in process S20has been removed by etching. Second chemical reinforcement may be performed on the portion where the chemically reinforced area has been removed. Since the second chemical enhancement may be performed in substantially the same manner as the first chemical enhancement, a detailed description will be omitted. Second chemical reinforcement may be performed on all surfaces as well as on the etched portion of the glass. However, since there are not many ions to be substituted in the portion where the reinforced area remains due to the first chemical reinforcement, there may be no significant difference in the chemical reinforcement depth before and after process S50is performed. For the portion where the chemically reinforced area is removed by etching, a new chemically reinforced area may be formed by second chemical reinforcement. The second chemical reinforcement process may proceed for a second period that is relatively shorter than the first period.

According to an example, the chemical reinforcement depth formed through the first chemical reinforcement and the chemical reinforcement depth formed through the second chemical reinforcement may be different. For example, the chemical reinforcement depth formed in the first chemical reinforcement may be greater than the chemical reinforcement depth formed in the second chemical reinforcement.

According to an example, in the first chemical enhancement process S20, the surface strength of the portion corresponding to the non-flexible area of the flexible display230may be reinforced, and in the second chemical enhancement process S50, the surface strength of the portion corresponding to the flexible area of the flexible display230may be reinforced. By performing separate processes on each portion, a different chemical reinforcement depth may be formed for each portion.

According to an example, in process S60, a process of cleaning the glass that has undergone the second chemical reinforcement process may be performed. In the cleaning process, a process of rinsing materials remaining on the surface of the transparent member may be performed. In the cleaning process, a healing process for surface treatment of the transparent member may be performed. In the healing process, the surface of the transparent member may be dissolved or etched by a healing liquid.

FIGS.6A,6B,6C,6D, and6Eare cross-sectional views illustrating a manufacturing process of a transparent member according to various embodiments of the disclosure.

FIGS.6A,6B,6C,6D, and6Eare cross-sectional views illustrating a characteristic portion of the transparent member300according to various embodiments of the disclosure. For convenience of description, the thickness of the transparent member300may be somewhat exaggerated. The transparent member300manufactured through the processes ofFIGS.6A,6B,6C,6D, and6Emay be disposed on the display panel of the flexible display (e.g., the flexible display230ofFIG.4A) ofFIG.4A. Like the flexible display230, the display panel may include a flexible area (e.g., the second area230b) and a non-flexible area (e.g., the first area230a) adjacent to the flexible area.

FIG.6Amay correspond to process S10ofFIG.5. If the base glass is cut to an appropriate size, a base layer301overall having a constant thickness is formed.

FIG.6Bmay correspond to process S20ofFIG.5. First chemical reinforcement may be performed on the surface of the base layer301overall having a constant thickness. During the first chemical reinforcement, chemical reinforcement may be performed not only on an upper surface300aand a lower surface300bof the base layer301, but also on a side surface connecting the upper surface300aand the lower surface300b. In the first chemical reinforcement process, e.g., a relatively large ion E1may be substituted with a relatively small ion E2in the base layer301. For example, the relatively large ion may be K+, and the relatively small ion may be Na+, but is not limited thereto.

After the first chemical reinforcement process, a first area311having a predetermined reinforcement depth may be formed on all surfaces of the base layer301.

FIG.6Cmay correspond to process S30ofFIG.5. In order to perform etching only on a specific portion, a masking member M may be disposed or attached on a portion of the surface of the first area311or the base layer301. The portion where the masking member M is disposed or attached may not be etched.

According to an example, the masking member may be disposed or attached to a first area (e.g., the first area230aofFIG.4A) of the flexible display (e.g., the flexible display230ofFIG.4A) or a portion (hereinafter, referred to as a first glass portion310) corresponding to the non-flexible area of the surface of the base layer301.

According to an example, the masking member may not be disposed or attached to a second area (e.g., the second area230bofFIG.4A) of the flexible display230or a portion (hereinafter, referred to as a second glass portion320) corresponding to the flexible area of the surface of the base layer301, and thus recesses322aand322bmay be formed by shape etching. In the second glass portion320, a first recess322aand a second recess322bmay be formed in an upper side and a lower side, respectively, by shape etching. The first recess322amay be a recess formed by being etched from the upper surface300a, and the second recess322bmay be a recess formed by being etched from the lower surface300b. However, it is not limited thereto, and a groove may be formed by etching only on either the upper or lower side of the base layer301. For example, one of the first groove322aor the second groove322bmay be omitted.

By forming recesses in the upper and lower sides of the second glass portion320, the two first glass portions310disposed on two opposite sides of the second glass portion320may be physically separated from each other. By forming recesses322aand322bin the upper and lower sides of the second glass portion320, stress may be dispersed to the two first glass portions310. When any one of the first recess322aand the second recess322bis omitted, stress may be unevenly dispersed, causing warpage. For example, if the second recess322bis omitted, the first glass portions310and the second glass portion320may form the same plane on the lower surface of the transparent member300, so that stress may not be evenly dispersed, causing warpage.

FIG.6Dmay correspond to process S40ofFIG.5. After the shape etching process is finished, the masking member M may be removed to prepare for the second chemical reinforcement process. When the masking member M is not used for shape etching, the process ofFIG.6Dmay be omitted.

FIG.6Emay correspond to process S50ofFIG.5. After etching, a second chemical reinforcement process may be performed on the transparent member300. The second chemical reinforcement process may have a different process temperature and time from those of, e.g., the first chemical process. The second chemical reinforcement process may be performed on all portions of the transparent member300. However, since the first glass portion310, which is an unetched portion, still has the first area311formed by the first chemical process, and the first area311has already been ion-substituted, the second chemical reinforcement process may make no significant difference in the chemical reinforcement depth. The surface of the second glass portion320, which is the etched portion, may be a surface that is not chemically reinforced. A second area321may be formed on the surface of the second glass portion320by ion substitution in the second chemical reinforcement process.

As illustrated in process S50ofFIGS.6E and5, the degree of chemical reinforcement of the second glass portion320, which is relatively thin, may be determined by the second chemical reinforcement process regardless of the degree of chemical reinforcement of the surface of the first glass portion310in the first chemical reinforcement process.

FIGS.6A,6B,6C,6D, and6Eillustrate a process for manufacturing a transparent member according to an embodiment of the disclosure. Various shapes of transparent members may be manufactured using the process ofFIG.5. Various shapes are described below.

FIG.7Ais a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.FIG.7Bis a cross-sectional view of a transparent member on which a resin is disposed inFIG.7A.

The transparent member300ofFIG.7AandFIG.7Bmay be a cross section of the transparent member300with respect to the cross section taken along line V1-V1′ of the flexible display (e.g., the flexible display230ofFIG.4A) ofFIG.4A. For convenience of description, the thickness of the transparent member300may be somewhat exaggerated inFIG.7AandFIG.7B.

Referring toFIG.7AandFIG.7B, the transparent member300may include a first glass portion310and a second glass portion320. The first glass portion310may extend from one edge of the second glass portion320. The second glass portion320may be disposed, e.g., between two first glass portions310.

According to an example, the first glass portion310may correspond to a non-flexible area of the flexible display230or a display panel (not shown). The first glass portion310may have a first thickness T1. Here, the first thickness T1may refer to a length between the upper surface300aand the lower surface300bof the transparent member300in the first glass portion310. Alternatively, the first thickness T1may refer to the length of the first glass portion310in the Z1-axis direction. The first thickness T1may be larger than, e.g., the second thickness T3. The first thickness T1may be, e.g., 50 μm to 500 μm, but is not limited thereto.

According to an example, the first glass portion310may include a first area311. The first area311may have a first depth T2. Here, the first depth T2may refer to the length of the chemically reinforced area from the surface of the first glass portion310. The first depth T2may be determined, e.g., in the first chemical reinforcement process S20ofFIG.5. For example, the first depth T2may refer to an average depth measured based on a surface of the first glass portion310. The first depth T2may have, e.g., a length of 5% to 20% of the first thickness T1, but is not limited thereto.

According to an example, the second glass portion320may correspond to a flexible area of the flexible display230or a display panel (not shown). The second glass portion320may have a second thickness T3. Here, the second thickness T3may refer to a length between the upper surface300aand the lower surface300bof the transparent member300in the second glass portion320. Alternatively, the second thickness T3may refer to the length of the second glass portion320in the Z1-axis direction. The second thickness T3may be smaller than, e.g., the first thickness T1. The second thickness T3may be, e.g., 30 μm to 60 μm, but is not limited thereto.

According to an example, the second glass portion320may include a second area321. The second area321may have a second depth T4different from the first depth T2. Here, the second depth T4may refer to the length of the chemically reinforced area from the surface of the second glass portion320. For example, the second depth T4may refer to an average depth measured based on a surface of the first glass portion320. The second depth T4may be determined, e.g., in the second chemical reinforcement process S50ofFIG.5. The second depth T4may have, e.g., a length of 5% to 20% of the second thickness T3, but is not limited thereto.

According to an example, the second glass portion320may include recesses322aand322bformed in the upper side and the lower side. The recesses322aand322bmay include, e.g., a first recess322ain the second glass portion320toward the upper surface300aof the transparent member300and a second recess322bin the second glass portion320toward the lower surface300bof the transparent member300. In the second glass portion320, recesses322aand322bmay be formed in the upper and lower sides, thereby forming a top-bottom notch structure. According to an embodiment of the disclosure, by forming recesses322aand322bin both upper and lower sides of the second glass portion320, stress may be dispersed to the first glass portions310positioned on two opposite sides of the second glass portion320. However, it is not limited thereto, and one of the first grooves322aand the second grooves322bmay be omitted from the second glass portion320. That is, only one of the first groove322aand the second groove322bcan be formed by an etching process.

According to an example, the first recess322amay have a depth greater than the first depth T2. According to an example, the second recess322bmay have a depth greater than the first depth T2. As the first recess322aand the second recess322bare etched to be deeper than the first depth T2, the entire first area may be removed from the second glass portion320.

According to an example, in the unfolding state of the transparent member300, the upper surface of the first glass portion310and the upper surface of the second glass portion320may be positioned on different planes. Due to the first recess322aformed in the upper side of the second glass portion320, the upper surface of the second glass portion320may not be included in the plane including the upper surface of the first glass portion310. For example, the upper surface of the second glass portion320may not be included in the plane including the upper surface of the first glass portion310. In other words, for example, the upper surface of the second glass portion320may not be on the same plane as the upper surface of the first glass portion310. Here, the upper surface of the first glass portion310may be the upper surface300aof the transparent member300. Here, the unfolding state of the transparent member300may refer to a state in which no bend exists in all areas of the transparent member300.

According to an example, in the unfolding state of the transparent member300, the lower surface of the first glass portion310and the lower surface of the second glass portion320may be positioned on different planes. Due to the second recess322bformed in the lower side of the second glass portion320, the lower surface of the second glass portion320may not be included in the plane including the lower surface of the first glass portion310. For example, the lower surface of the second glass portion320may not be included in the plane including the lower surface of the first glass portion310. In other words, for example, the lower surface of the second glass portion320may not be on the same plane as the lower surface of the first glass portion310. Here, the lower surface of the first glass portion310may be the lower surface300bof the transparent member300.

According to an example, the first depth T2and the second depth T4may be different in size. For example, the first depth T2may be greater than the second depth T4. According to an example, the ratio of the first depth T2to the first thickness T1may be substantially the same as the ratio of the second depth T4to the second thickness T3. For example, when the first thickness T1is 50 μm, and the second thickness T3is 30 μm, the first depth T2may be 7.5 μm, and the second depth may be 4.5 μm. By allowing the ratio of the first depth T2to the first thickness T1in the first glass portion310to be substantially the same as the ratio of the second depth T4to the second thickness T3in the second glass portion320, the difference in expansion rate between the first glass portion310and the second glass portion320may be minimized. By minimizing the difference in the expansion rate between the first glass portion310and the second glass portion320having the different thicknesses, it is possible to prevent warpage that may occur in the transparent member300(especially the second glass portion320).

According to an example, the second glass portion320may be formed to be horizontally symmetrical with respect to a virtual plane C that is perpendicular to the thickness direction of the transparent member300and passes through the transparent member300. Here, the horizontal symmetry may mean that the second glass portion320is positioned in an area not affected by the first depth T2.

The virtual plane C may be, e.g., a plane perpendicular to the thickness direction of the transparent member300and dividing the average thickness of the transparent member300by half, but is not limited thereto. The virtual plane C may be, e.g., a plane perpendicular to the thickness direction of the transparent member300and dividing the average thickness of the first glass portion310by half, but is not limited thereto. Here, the thickness direction may refer to the Z1-axis direction. Alternatively, the thickness direction may refer to a direction from the lower surface300bof the transparent member300to the upper surface300aof the transparent member300.

By forming the second glass portion320horizontally symmetrically with respect to the virtual plane C, stress may be evenly dispersed to the first glass portions310positioned on two opposite sides of the second glass portion320.

According to an example, the boundary between the first glass portion310and the second glass portion320may have a surface/plane level difference (e.g., step or bump).

According to an example, although not illustrated, the transparent member300may further include a refractive index matching portion. For example, the refractive index matching portion may be disposed around at least one of the first glass portion310or the second glass portion320to match the refractive indexes of light formed by the difference in thickness between the first glass portion310and the second glass portion320. The refractive index matching portion may be formed of, e.g., a transparent material. The refractive index matching portion may be formed of, e.g., a urethane-based, acrylic-based, or silicon-based material. The refractive index matching portion may have substantially the same refractive index as that of the base layer301.

Referring toFIG.7B, the transparent member300may further include a resin portion340. The resin portion340may be disposed on the second glass portion320of the transparent member300. The resin portion340may be arranged to fill the groove formed in the second glass portion320. The resin portion340may include a first resin portion340aand a second resin portion340b. The first resin portion340amay be filled in the first groove322a. The second resin portion340bmay be filled in the second groove322b. The resin portion340may be filled, for example, in at least one of the first groove322aor the second groove322b. By filling at least one of the first groove322aor the second groove322bwith the resin portion340, the step between the upper surface300aand the lower surface300bof the transparent member300can be removed.

The resin portion340shown inFIG.7Bmay be a portion of the first adhesive member (e.g., the first adhesive member inFIG.4b) or a portion of the second adhesive member (e.g., the second adhesive member inFIG.4b) when the transparent member300is included in the flexible display (e.g., the flexible display230inFIG.4b). For example, the first resin portion340amay be a portion of the first adhesive member P1. For example, the second resin portion340bmay be a portion of the second adhesive member P2.

Hereinafter, transparent members according to various embodiments of the disclosure, which may be manufactured using the manufacturing process ofFIG.5, are described with reference toFIGS.8to10,11A,11B,11C, and12to14.

FIG.8is a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

A transparent member300-1ofFIG.8may be a cross section of the transparent member300-1with respect to the cross section taken along line V1-V1′ of the flexible display (e.g., the flexible display230ofFIG.4A) ofFIG.4A. InFIG.8, the thickness of the first glass portion310, the first depth of the first area311, the thickness of the second glass portion320-1, and the second depth of the second area321-1have been described with reference toFIG.7Aand are not described below. A detailed description of the components described with reference toFIG.7Aamong the components ofFIG.8will be omitted. For convenience of description, the thickness of the transparent member300-1may be somewhat exaggerated inFIG.8.

Referring toFIG.8, the transparent member300-1according to an embodiment is entirely the same as or similar to the transparent member300ofFIG.7but is different in that the transparent member300-1further includes a third portion330. The following description focuses primarily on the differences.

According to an example, the third portion330may be disposed between the first glass portion310and the second glass portion320-1. The third portion330may be disposed so that one side contacts an edge of the first glass portion310and the other side contacts an edge of the second glass portion320-1. The third portion330may have an inclined slope. The third portion330may be formed to be inclined downward from, e.g., the first glass portion310toward the second glass portion320-1. The third portion330may be formed to be inclined to connect, e.g., the first glass portion310and the second glass portion320-1. The slope of the third portion330may have, e.g., a flat slope or a curved slope.

According to an example, the third portion330may be formed by the etching process S30ofFIG.5. In the etching process S30, the upper recess322a-1and the lower recess322b-1may be formed around the second glass portion320-1and the third portion330. Accordingly, the chemical enhancement depth of the third portion330may be the same as or similar to the chemical enhancement depth of the second glass portion320-1.

By adding the third portion330to the boundary between the first glass portion310and the second glass portion320-1of the transparent member300-1, the thickness of the base layer301may be gradually changed to enhance visibility of the transparent member300-1.

FIG.9is a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

The transparent member300-2ofFIG.9may be a cross section of the transparent member300-2with respect to the cross section taken along line V1-V1′ of the flexible display (e.g., the flexible display230ofFIG.4A) ofFIG.4A. InFIG.9, the thickness of the first glass portion310, the first depth of the first area311, the thickness of the second glass portion320-2, and the second depth of the second area321-2have been described with reference toFIG.7A, and are not described below. A detailed description of the components described with reference toFIG.7Aamong the components ofFIG.9will be omitted. For convenience of description, the thickness of the transparent member300-2may be somewhat exaggerated inFIG.9.

Referring toFIG.9, the transparent member300-2according to an embodiment is entirely the same as or similar to the transparent member300ofFIG.7A, but is different in the shape of the second glass portion320-2. The following description focuses primarily on the differences.

According to an example, one surface of the second glass portion320-2of the transparent member300-2may have a pattern in which a concave portion324and the convex portion323are alternately disposed. For example, at least one of the upper surface or the lower surface of the second glass portion320-2may have a pattern in which the concave portion324and the convex portion323are alternately disposed. For example, the pattern shapes of the upper and lower surfaces of the second glass portion320-2may be formed to be horizontally symmetrical.

According to an example, a boundary between the concave portion324and the convex portion323may be formed to have a surface/plane level difference (e.g., step or bump) vertically. For example, the alternating patterns of the concave portion324and the convex portion323may have a cross section having a rectangular wave shape as a whole.

According to an example, the surface pattern of the second glass portion320-2may be formed by the etching process S30ofFIG.5. In the etching process S30, the upper recess322a-2and the lower recess322b-2may be formed around the second glass portion320-2.

According to an example, bending performance and/or impact strength performance may be enhanced by alternately disposing the concave portion324and the convex portion323in the second glass portion320-2. For example, impact strength performance may be enhanced by the convex portion323. For example, bending performance may be enhanced by the concave portion324.

FIG.10is a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

The transparent member300-3ofFIG.10may be a cross section of the transparent member300-3with respect to the cross section taken along line V1-V1′ of the flexible display (e.g., the flexible display230ofFIG.4A) ofFIG.4A. InFIG.10, the thickness of the first glass portion310, the first depth of the first area311, the thickness of the second glass portion320-3, and the second depth of the second area321-3have been described with reference toFIG.7Aand are not described below. A detailed description of the components described with reference toFIG.7Aamong the components ofFIG.10will be omitted. For convenience of description, the thickness of the transparent member300-3may be somewhat exaggerated inFIG.10.

Referring toFIG.10, the transparent member300-3according to an embodiment is entirely the same as or similar to the transparent member300ofFIG.7A, but is different in the shape of the second glass portion320-3. The following description focuses primarily on the differences.

According to an example, one surface of the second glass portion320-3of the transparent member300-3may have a pattern in which a concave portion326and a convex portion325are alternately disposed. For example, at least one of the upper surface or the lower surface of the second glass portion320-3may have a pattern in which the concave portion326and the convex portion325are alternately disposed. For example, the pattern shapes of the upper and lower surfaces of the second glass portion320-3may be formed to be horizontally symmetrical.

According to an example, the alternating pattern of the concave portion326and the convex portion325may have a wave-shaped cross section. For example, the alternating patterns of the concave portion326and the convex portion325may overall have a curved shape.

According to an example, the surface pattern of the second glass portion320-3may be formed by the etching process S30ofFIG.5. In the etching process S30, the upper recess322a-3and the lower recess322b-3may be formed around the second glass portion320-3.

According to an example, bending performance and/or impact strength performance may be enhanced by alternately disposing the concave portion326and the convex portion325in the second glass portion320-3. For example, impact strength performance may be enhanced by the convex portion325. For example, bending performance may be enhanced by the concave portion326.

FIGS.11A and11Bare views illustrating a transparent member according to various embodiments of the disclosure.

FIG.11Ais a top view of a transparent member300-4according to an embodiment of the disclosure.FIG.11Bis a cross-sectional view of a transparent member300-4taken along line V2-V2′ according to an embodiment of the disclosure.

InFIGS.11A and11B, the thickness of the first glass portion310, the first depth of the first area311, the thickness of the second glass portion320-4, and the second depth of the second area321-4have been described with reference toFIG.7A, and are not described below. A detailed description of the components described with reference toFIG.7Aamong the components ofFIGS.11A and11Bwill be omitted.

Referring toFIGS.11A and11B, the transparent member300-4according to an embodiment is entirely the same as or similar to the transparent member300ofFIG.7A, but is different in the shape of the second glass portion320-4. The following description focuses primarily on the differences.

According to an example, the second glass portion320-4of the transparent member300-4may be formed by penetrating a portion thereof. The second glass portion320-4may be formed to be symmetrical with respect to the folding axis F but is not limited thereto.

According to an example, the second glass portion320-4may include a through hole327. For example, the through hole327may be formed to be symmetrical with respect to the folding axis F but is not limited thereto. The through hole327may be formed to extend in a direction parallel to the folding axis F. A plurality of through-holes327may be disposed to be spaced apart from each other by a predetermined interval along a direction perpendicular to the folding axis F.

According to an example, the second glass portion320-4may include a second area321-4. The second area321-4may be formed not only on the upper surface and the lower surface of the second glass portion320-4but also on the surrounding surface of the through-hole327.

According to an example, the pattern of the through hole327of the second glass portion320-4may be formed by the etching process S30ofFIG.5. In the etching process S30, the upper recess322a-4and the lower recess322b-4, as well as the through-hole327, may be formed around the second glass portion320-4.

As illustrated, a through hole may be formed in the second glass portion320-4to enhance bending performance of the transparent member300-4.

FIG.11Cis a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

Referring toFIG.11C, the thickness of the first glass portion310, the first depth of the first area311, the thickness of the second glass portion320-4′, and the second depth of the second area321-4′ have been described with reference toFIG.7A, and are not described below. A detailed description of the components described with reference toFIG.7Aamong the components ofFIG.11Cwill be omitted.

The transparent member300-4′ illustrated inFIG.11Cmay have a shape that is the same as or similar to the shape in the planar view of the transparent member300-4illustrated inFIG.11A. The transparent member300-4′ illustrated inFIG.11Cis similar to the transparent member300-4described with reference toFIGS.11A and11Bin that a plurality of through-holes327′ are formed in the second glass portion320-4′. The description of the shape or pattern of the through-hole327′ ofFIG.11Cis replaced with the description of the through-hole327made with reference toFIGS.11Aand11B. Referring toFIG.11C, unlike other embodiments of the disclosure, the thickness of the second glass portion320-4′ of the transparent member300-4′ may be substantially the same as the thickness of the first glass portion310. The bending performance of the second glass portion320-4′ may be enhanced by forming a plurality of through-holes327′ while maintaining the same thickness as that of the first glass portion310.

According to an example, the upper surface and the lower surface of the second glass portion320-4′ of the transparent member300-4′ may be formed of the first area311. Here, the upper surface of the second glass portion320-4′ may be a surface corresponding to the upper surface300aof the transparent member300-4′. Here, the lower surface of the second glass portion320-4′ may be a surface corresponding to the lower surface300bof the transparent member300-4′. In the etching process S30ofFIG.5, since etching for forming recesses is not performed on the upper and lower surfaces of the second glass portion320-4′, the first chemically reinforced area311formed by the first chemical reinforcement S20may remain on the upper and lower surfaces of the second glass portion320-4′.

According to an example, the vertical surface of the second glass portion320-4′ of the transparent member300-4′ may be formed of the second area321-4′. Here, the vertical surface of the second glass portion320-4′ may refer to a surface in contact with the through-hole327′. A second area321-4′ that is thinner than the first area311may be formed on the vertical surface of the second glass portion320-4′. Accordingly, even if the width is reduced by the plurality of through-holes327′, the strength of the transparent member300-4′ may be enhanced by forming a thin second area321-4′ corresponding thereto by using the manufacturing process ofFIG.5.

FIG.12is a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

For convenience of description, the thickness of the transparent member300-5may be somewhat exaggerated inFIG.12.

Referring toFIG.12, the transparent member300-5may include a first transparent member300a-5and a second transparent member300b-5. The first transparent member300a-5may correspond to, e.g., substantially all areas of the flexible display (e.g., the flexible display230ofFIG.4A). For example, at least a portion of the second transparent member300b-5may correspond to a first area (e.g., the first area230aofFIG.4A) of the flexible display230. The transparent member300-5may have a two-level stacked structure in which the second transparent member300b-5is partially stacked on the first transparent member300a-5. The refractive indices of the first transparent member300a-5and the second transparent member300b-5may be substantially the same but are not limited thereto.

According to an example, the transparent member300-5may include a first glass portion310-5corresponding to a non-flexible area of the flexible display230, a second glass portion320-5corresponding to a portion of the flexible area of the flexible display230, and a third portion330-5connecting the first glass portion310-5and the second glass portion320-5. For example, at least a portion of the third portion330-5may be positioned near an edge of a second area (e.g., the second area230bofFIG.4A) of the flexible display230.

According to an example, the first transparent member300a-5may include a first area301a-5near a surface thereof. The first area301a-5may have, e.g., substantially the same reinforcement depth throughout the entire surface of the first transparent member300a-5.

According to an example, the second transparent member300b-5may include a second area301b-5formed in a portion corresponding to the first glass portion310-5and a third reinforced area302b-5corresponding to the third portion330-5. The reinforcement depth of the second area301b-5may be substantially the same as, e.g., the reinforcement depth of the first area301a-5, but is not limited thereto. The reinforcement depth of the third reinforced area302b-5may be smaller than the reinforcement depth of the second area301b-5.

According to an example, the shape of the portion corresponding to the third portion330-5of the second transparent member300b-5may be formed by the etching process S30ofFIG.5. The third reinforced area302b-5formed in the third portion330-5of the second transparent member300b-5may be formed by the second chemical reinforcement process S50ofFIG.5.

By forming an inclined surface on the third portion330-5of the second transparent member300b-5, visibility of a boundary between the first glass portion310-5and the second glass portion320-5may be enhanced.

FIG.13is a plan view illustrating a flexible display folded multiple times according to an embodiment of the disclosure.

Referring toFIG.13, a flexible display230-1may have a plurality of folding axes F1and F2. For example, the folding axes F1and F2may include a first folding axis F1and a second folding axis F2spaced apart from each other. The first folding axis F1and the second folding axis F2may be parallel to each other, for example.

According to an example, the flexible display230-1may include a plurality of first areas230a-1and a plurality of second areas230b-1. The plurality of second areas230b-1may be formed around, e.g., the first folding axis F1and the second folding axis F2, respectively. The plurality of first areas230a-1may be formed to extend from, e.g., the second area230b-1. The first area230a-1may refer to a flat area or a non-flexible area that maintains a flat surface even when the flexible display230-1is folded about the folding axes F1and F2. The second area230b-1may refer to a bending area or a flexible area that is bent when the flexible display230-1is folded about the folding axes F1and F2.

The flexible display230-1may include a display panel and a transparent member (e.g., a transparent member300-6ofFIG.14). Like the flexible display230-1, the display panel may include a flexible area (e.g., the second area230b-1) and a non-flexible area (e.g., the first area230a-1) adjacent to the flexible area.

The display panel may be provided to display an image. The display panel may be, e.g., a light emitting display panel. The display panel may be, e.g., an organic light emitting display panel or a quantum dot light emitting display panel. The light emitting layer of the organic light emitting display panel may include an organic light emitting material. The light emitting layer of the quantum dot light emitting display panel may include quantum dots and quantum rods. The display panel may be flexible.

The transparent member300-6(or window) may be disposed on, e.g., the display panel. Different components (e.g., input detection units) may be disposed on the transparent member300-6and the display panel. The transparent member300-6may include an optically transparent insulating material. Accordingly, the image generated by the display panel may be easily transferred to the user through the transparent member300-6.

The transparent member300-6may transmit the image from the display panel while mitigating the external impact, thereby preventing the display panel from being damaged or malfunctioning due to the external impact. Here, the external impact is a force applied from the outside, such as pressure and stress, and may refer to a force that causes damage to the display panel.

FIG.14is a cross-sectional view illustrating a transparent member included in a flexible display ofFIG.13according to an embodiment of the disclosure.

The transparent member300-6ofFIG.14may be a cross section of the transparent member300-6with respect to the cross section taken along line V3-V3′ of the flexible display (e.g., the flexible display230-1ofFIG.13) ofFIG.13. InFIG.14, the thickness of the first glass portion310-6, the first depth of a first area311-6, the thickness of the second glass portion320-6, and the second depth of a second area321-6have been described with reference toFIG.7Aand are not described below. A detailed description of the components described with reference toFIG.7Aamong the components ofFIG.14will be omitted. For convenience of description, the thickness of the transparent member300-6may be somewhat exaggerated inFIG.14.

Referring toFIG.14, the transparent member300-6may include a plurality of first glass portions310-6and a plurality of second glass portions320-6. The first glass portion310-6may extend from one edge of the second glass portion320-6. One second glass portion320-6may be disposed, e.g., between two adjacent first glass portions310-6.

According to an example, the first glass portion310-6may correspond to a non-flexible area of the flexible display230-1or a display panel (not shown). According to an example, the second glass portion320-6may correspond to a flexible area of the flexible display230-1or a display panel.

According to an example, the second glass portion320-6may include an upper recess322a-6and a lower recess322b-6. As the upper recess322a-6and the lower recess322b-6are formed, internal stress may be evenly dispersed to the two first glass portions310-6positioned on two opposite sides of the second glass portion320-6. The second glass portion320-6may be formed to be horizontally symmetrical for even stress dispersion.

The flexible display230-1and the transparent member300-6that are folded twice have been described with reference toFIGS.13and14, but this is merely an example, and a flexible display and a transparent member that are folded three or more times may also be implemented as described above.

FIGS.15A and15Bare front and rear views illustrating an electronic device in a closed state according to various embodiments of the disclosure.FIGS.16A and16Bare front and rear views illustrating an electronic device in an open state according to various embodiments of the disclosure.

InFIGS.15A and15B, orFIGS.16A and16B, an electronic device400may be at least partially similar to the electronic device101ofFIG.1or may further include other embodiments of the electronic device101.

Referring toFIGS.15A and15B, orFIGS.16A and16B, an electronic device400according to an embodiment may include a first housing410(e.g., a first housing structure or a base housing) or a second housing420(e.g., a second housing structure or a slide housing). The electronic device400may include a flexible display430(e.g., an expandable display, a stretchable display, a rollable display, or a display assembly) (e.g., the display module160ofFIG.1) fastened to be slidable or rollable. The electronic device400may have a structure in which at least two housings are stacked front to rear to be slidable in a designated direction (e.g., a left-right direction or an upper-lower direction). For example, as one housing slides along another housing in a designated direction (e.g., the left-right direction or the upper-lower direction), the display area of the flexible display430may vary.

For example, the second housing420may be coupled to the first housing410to be movable in a designated direction (e.g., the X2-axis direction (the right direction)) and within a designated distance from the first housing410. The flexible display430may be disposed on the front surface of the electronic device400to be supported through at least a portion of the first housing410and the second housing420.

The electronic device400may switch from the open state (stretched state, unbended state or first state) to the closed state (bended state or second state) as at least a portion of the second housing420is received in a first receiving portion4101of the first housing410. Here, the first receiving portion4101may refer to a space formed inside the first housing410. The electronic device400may switch from the closed state to the open state as at least the portion of the second housing420, received in the first receiving portion4101, is slid out of the first receiving portion4101. The open state may refer to, e.g., a state in which the second area430bof the flexible display430is maximized, and the closed state may refer to, e.g., a state in which the second area430bof the flexible display430is minimized. Alternatively, the open state may refer to a state in which the second housing420is maximally slid out (roll-out or draw-out) of the first housing410, and the closed state may refer to a state in which the second housing420is maximally slid in (roll-in or draw-in) to the first housing410.

The electronic device400may lead to the display area of the flexible display430being varied by sliding the second housing420along a designated direction (e.g., the X2-axis direction (direction {circle around (2)}) or the −X2-axis direction (direction {circle around (1)})) from the first housing410.

The display area of the flexible display430may vary depending on the slide-in operation (e.g., the movement in the X2-axis direction (direction {circle around (2)})) or the slide-out operation (e.g., the movement in the −X2-axis direction (direction {circle around (1)})). The flexible display430may perform, e.g., a slide-in operation or a slide-out operation by an external force (e.g., the user's manipulation) or an internal force (e.g., a separate driving module provided therein). The slide-in operation may be a series of operations for reducing the size of the display area by the flexible display430. The slide-out operation may be a series of operations for increasing the size of the display area by the flexible display430. Hereinafter, for convenience of description, a state in which the display area of the flexible display430is maximized by the slide-out operation is referred to as an open state, and a state in which the display area of the flexible display430is minimized by the slide-in operation is referred to as a closed state. For convenience of description, in the following description, the state of the flexible display430before the slide-in or slide-out operation commences is denoted as a first state or an initial state, and the state of the flexible display430after the slide-in or slide-out operation has been done is denoted as a second state or a switching state.

The flexible display430may be disposed so that a first area430acorresponding to at least a portion is not received in the first receiving portion4101of the first housing410or the second receiving portion4201of the second housing420. Here, the first area430amay refer to a flat area disposed to be always visible from the outside regardless of whether the flexible display430is slid in or out. The first area430amay be used, e.g., for the electronic device400to display an image according to an operation on the front surface. The first area430aof the flexible display430may be disposed to be visible from the outside (e.g., the front surface).

In the flexible display430, the second area430bcorresponding to at least a portion may be received in the first receiving portion4101of the first housing410or the second receiving portion4201of the second housing420. Here, the second area430bmay be an area in which an area visible from the outside varies according to the slide-in or slide-out of the flexible display430. The second area430bmay be deactivated not to be used to display the image according to the operation of the electronic device400or activated to be used to display the image according to the operation, on the rear surface, of the electronic device400. The second area430bof the flexible display430received in the receiving portion (e.g., the first receiving portion4101or the second receiving portion4201) may be disposed to be visible from the outside or to be visible from the rear surface alone, but not from the front surface. The size of the second area430bmay be increased by the slide-out operation or decreased by the slide-in operation. The second area430bmay be activated to be used to display the image according to the operation of the electronic device400, only on the portion visible from the outside as at least a portion is slid out.

The electronic device400may include a front surface400a(e.g., a first surface), a rear surface400b(e.g., a second surface) facing away from the front surface400a, and a side surface (not shown) surrounding a space between the front surface400aand the rear surface400b. The side surface may be at least one of an upper surface, a lower surface, a left surface, or a right surface with respect to the front surface400a. However, this is an example, and a first side member411and a second side member421may have surfaces corresponding to one or two of the four surfaces of the first housing410and the second housing420. Hereinafter, for convenience of description, a case of having three surfaces is described as an example.

The electronic device400may include a first housing410and a second housing420. The first housing410may include a first side member411. The second housing420may include a second side member421. The first side member411may form an edge corresponding to at least three surfaces (e.g., the upper, lower, and right surfaces of the front surface) among the four surfaces of the first housing410. The second side member421may form an edge corresponding to at least three surfaces (e.g., the upper, lower, and left surfaces of the front surface) among the four surfaces of the second housing420.

The first side member411may include at least one of a first side surface4111(e.g., a lower surface of the first housing410), a second side surface4112(e.g., a right surface of the first housing410), or a third side surface4113(e.g., an upper surface of the first housing410) with respect to the front surface. The first side surface4111may have a first length along a first direction (e.g., X2-axis direction). The second side surface4112may extend to have a second length longer than the first length along a direction (e.g., Y2-axis direction) substantially perpendicular to the first side surface4111. The third side surface4113may extend substantially parallel to the first side surface4111from the second side surface4112and may have the first length. The first side member411may be, e.g., at least partially formed of a conductive material (e.g., metal). The first side member411may include, e.g., a first supporting member412extending to at least a portion of the first receiving unit4101of the first housing410.

The second side member421may include at least one of a fourth side surface4211(e.g., a lower surface of the second housing420), a fifth side surface4212(e.g., a left surface of the second housing420), or a sixth side surface4213(e.g., an upper surface of the second housing420) with respect to the front surface. The fourth side surface4211at least partially corresponds to the first side surface4111and may have a third length. The fifth side surface4212may extend substantially parallel to the second side surface4112from the fourth side surface4211and may have a fourth length larger than the third length. The sixth side surface4213may extend substantially parallel to the third side surface4113from the fifth side surface4212and may have the third length. The second side member421may be, e.g., at least partially formed of a conductive material (e.g., metal). The second side member421may include, e.g., a second supporting member422extending to at least a portion of the second receiving unit4201of the second housing420.

The first side surface4111and the fourth side surface4211or the third side surface4113and the sixth side surface4213may be coupled to be slidable on each other. In this case, the whole or part of the fourth side surface4211overlaps the first side surface4111and may thus be disposed to be substantially invisible from the outside. Further, the whole or part of the sixth side surface4213overlaps the third side surface4113and may thus be disposed to be substantially invisible from the outside. For example, the fourth side surface4211or the sixth side surface4213may be disposed to be at least partially visible from the outside in the closed state.

When slid in, the second supporting member422included in the second side member421overlaps the first supporting member412included in the first side member411and may thus be disposed to be substantially invisible from the outside. For example, in a state not fully slid in, a portion of the second supporting member422may overlap the first supporting member412to be invisible from the outside, and the rest of the second supporting member422may be disposed not to overlap the first supporting member412to be visible from the outside.

The electronic device may include a rear cover413. The rear cover413may be disposed on at least a portion of the first housing410, on the rear surface400bof the electronic device. The rear cover413may be disposed through at least a portion of, e.g., the first supporting member412. The rear cover413may be formed integrally with, e.g., the first side member411. The rear cover413may be formed of, e.g., polymer, laminated or colored glass, ceramic, metal (e.g., aluminum, stainless steel (STS), or magnesium), or a combination of at least two thereof. The rear cover413may extend, e.g., to at least a portion of the first side member411. At least a portion of the first supporting member412may be replaced with, e.g., the rear cover413. The electronic device400may further include another rear cover (e.g., second rear cover) which is disposed on, or replaced with, at least a portion of the second supporting member422, in the second housing420.

The electronic device400may include a flexible display430disposed to be supported by at least a portion of the first housing410or the second housing420. The flexible display430may include a first area430a(e.g., flat portion) and/or a second area430b(e.g., a bent portion, a bendable portion, or a rolling portion). The first area430amay be an area that is always visible from the outside of all areas of the flexible display430. When slid in, the second area430bwhich may extend from the first area430amay be received into the first receiving portion4101of the first housing410or the second receiving portion4201of the second housing420to be invisible from the outside and, when slid out, slid out of the first receiving portion4101or second receiving portion4201to be visible from the outside. The first area430amay be disposed to be supported by the first housing210. The area slid out of the first receiving portion4101or second receiving portion4201of the first area430aor the second area430b, may be activated to display an image, and the area received in the first receiving portion4101or second receiving portion4201, of the second area430bmay be deactivated to not display an image.

The second area430bof the flexible display430may extend from the first area430ain a state in which the second housing420is slid out in a designated direction (direction {circle around (1)}). To this end, the second area430bmay form substantially the same plane as the first area430aand may be disposed to be visible from the outside.

The second area430bof the flexible display430may be received in the second receiving portion4201of the second housing420to be invisible from the outside or to be invisible from the front while being visible from the back, in a state slid in along a designated direction (direction {circle around (2)}).

The first housing410and/or the second housing420may be operated to slide on each other so that the entire width is variable. As an example, in the closed state, the electronic device400may be configured to have a first width W1between the second side surface4112and the fifth side surface4212. Further, the electronic device400may be configured to have a third width W3that is larger than the first width W1as a whole by being moved to have the second width W2in the open state. In the closed state, the flexible display430included in the electronic device400may have a display area substantially corresponding to the first width W1and, in the open state, have an extended display area substantially corresponding to the third width W3.

The slide-in and/or slide-out operation of the electronic device400may be automatically performed. The electronic device400may receive, e.g., a slide-in or slide-out request and operate the driving module disposed therein. The slide-in or slide-out request may be performed through a designated operation button disposed in the electronic device400and/or through a touch to a corresponding object displayed on the flexible display430. As an example, upon detecting a slide-in and/or slide-out event, the processor (e.g., the processor120ofFIG.1) of the electronic device400may operate to control the slide of the second housing420through the driving module. The processor (e.g., the processor120ofFIG.1) of the electronic device400may operate to control the display screen of the flexible display430to execute an application program or display an object in various manners, corresponding to the changed display area of the flexible display430according to, e.g., the closed state, open state, or intermediate state (including, e.g., a free-stop state).

The electronic device400may include at least one of an input module (e.g., a microphone403), a sound output module (e.g., a receiver406for phone calls or speaker407), sensor modules404and417, a camera module (e.g., a first camera module405or a second camera module416), a connector port408, a key input device (not shown), or an indicator (not shown), disposed in the first receiving portion4101of the first housing410. The electronic device400may be configured to omit at least one of the above-described components or add other components. At least one of the above-described components may be disposed in the second receiving portion4201of the second housing420.

The input module may include a plurality of microphones disposed to detect the direction of sound. The sound output module may include, e.g., the receiver406for phone calls and the speaker407. In the open state, the speaker407may be disposed to face the outside through at least one speaker hole, formed in the first housing410. The connector port408may be disposed to face the outside through the connector port formed in the first housing410. The receiver406for phone calls may include a speaker (e.g., a piezo speaker) operated without a separate speaker hole.

The sensor modules404and417may generate an electrical signal or data value corresponding to an internal operating state or external environmental state of the electronic device400. The sensor modules404and417may include a first sensor module404(e.g., proximity sensor or illuminance sensor) disposed on the front surface400aof the electronic device400and/or a second sensor module417(e.g., heart rate monitoring (HRM) sensor) disposed on the rear sensor400b. The first sensor module404may be disposed under the flexible display430, e.g., on the front surface400aof the electronic device400. The first sensor module404and/or the second sensor module417may include at least one of the proximity sensor, the illuminance sensor, the TOF) sensor, the ultrasonic sensor, the fingerprint recognition sensor, the gesture sensor, the gyro sensor, the air pressure sensor, the magnetic sensor, the accelerometer, the grip sensor, the color sensor, the IR sensor, the biometric sensor, the temperature sensor, or the humidity sensor.

The camera module may include the first camera module405disposed on the front surface400aof the electronic device400and the second camera module416disposed on the rear surface400b. The first and/or second camera module405and416may include one or more lenses, an image sensor, and/or an ISP. For example, the first camera module405may be disposed under the flexible display430and be configured to capture a subject through a portion of the active area of the flexible display430. The flash418may be disposed on the second camera module416. The flash418may include, e.g., a light emitting diode (LED) or a xenon lamp.

The first camera module405among the camera modules or some sensor module404among the sensor modules404and417may be disposed to detect the external environment through the flexible display430. For example, the first camera module405or some sensor module404may be disposed to contact the external environment through an opening or a transmissive area formed in the flexible display430, in the first receiving portion4101of the first housing410. The area of the flexible display430facing the first camera module405may be a portion of the area displaying content and be formed as a transmissive area having a designated transmittance. The transmissive area may be formed to have a transmittance ranging from about 5% to about 20%. The transmissive area may include an area overlapping an effective area (e.g., an angle-of-view area) of the first camera module405through which light incident on the image sensor to obtain an image passes. For example, the transmissive area of the flexible display430may include an area having a lower pixel density and/or wiring density than the surrounding area. The transmissive area may replace the above-described opening. The camera module405may include an under display camera (UDC). The sensor module404may be disposed to perform its functions without being visually exposed through the flexible display430in the internal space of the electronic device400.

FIGS.17A and17Bare perspective views illustrating a flexible display according to various embodiments of the disclosure.

Referring toFIGS.17A and17B, the flexible display430may include a first area430aand a second area430bextending from the first area430a. The first area430amay refer to a flat area or a non-flexible area that maintains a flat surface even when the electronic device (e.g., the electronic device400ofFIG.15A) slides between the closed state and the open state. The second area430bmay refer to a bending area or a flexible area that is bent when the electronic device400slides between the closed state and the open state. The first area430aand the second area430bmay be disposed so that one surface of each area contacts one surface of the other area.

The flexible display430may include a display panel and a transparent member (e.g., a transparent member500ofFIG.18or the transparent member500-1ofFIG.19). Like the flexible display430, the display panel may include a flexible area (e.g., the second area430b) and a non-flexible area (e.g., the first area430a) adjacent to the flexible area.

The display panel may be provided to display an image. The display panel may be, e.g., a light emitting display panel, but is not limited thereto. The display panel may be, e.g., an organic light emitting display panel or a quantum dot light emitting display panel. The light emitting layer of the organic light emitting display panel may include an organic light emitting material. The light emitting layer of the quantum dot light emitting display panel may include quantum dots and quantum rods. The display panel may be flexible.

The transparent member500(or window) may be disposed on, e.g., the display panel. Different components (e.g., input detection units) may be disposed on the transparent member500and the display panel. The transparent member500may include an optically transparent insulating material. Accordingly, the image generated by the display panel may be easily transferred to the user through the transparent member500.

The transparent member500may transmit the image from the display panel while mitigating the external impact, thereby preventing the display panel from being damaged or malfunctioning due to the external impact. Here, the external impact is a force applied from the outside, such as pressure and stress, and may refer to a force that causes damage to the display panel.

FIG.18is a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

The transparent member500ofFIG.18may be a cross section of the transparent member500with respect to the cross section taken along line V4-V4′ of the flexible display (e.g., the flexible display430ofFIG.17B) ofFIG.17A. For convenience of description, the thickness of the transparent member500may be somewhat exaggerated inFIG.18.

Referring toFIG.18, the transparent member500may include a first glass portion510and a second glass portion520. The first glass portion510may extend from one edge of the second glass portion520.

According to an example, the first glass portion510may correspond to a non-flexible area of the flexible display430or a display panel (not shown). The first glass portion510may have a first thickness T1′. Here, the first thickness T1′ may refer to a length between the upper surface500aand the lower surface500bof the transparent member500in the first glass portion510. Alternatively, the first thickness T1′ may refer to the length of the first glass portion510in the Z2-axis direction. The first thickness T1′ may be larger than, e.g., the second thickness T3′. The first thickness T1′ may be, e.g., 50 μm to 500 μm, but is not limited thereto.

According to an example, the first glass portion510may include a first area511. The first area511may have a first depth T2′. Here, the first depth T2′ may refer to the length of the chemically reinforced area from the surface of the first glass portion510. The first depth T2′ may be determined, e.g., in the first chemical reinforcement process S20ofFIG.5. The first depth T2′ may have, e.g., a length of 5% to 20% of the first thickness T1′, but is not limited thereto.

According to an example, the second glass portion520may correspond to a flexible area of the flexible display430or a display panel (not shown). The second glass portion520may have a second thickness T3′. Here, the second thickness T3′ may refer to a length between the upper surface500aand the lower surface500bof the transparent member500in the second glass portion520. Alternatively, the second thickness T3′ may refer to the length of the second glass portion520in the Z2-axis direction. The second thickness T3′ may be smaller than, e.g., the first thickness T1′. The second thickness T3′ may be, e.g., 30 μm to 60 μm, but is not limited thereto.

According to an example, the second glass portion520may include a second area521. The second area521may have a second depth T4′ different from the first depth T2. Here, the second depth T4′ may refer to the length of the chemically reinforced area from the surface of the second glass portion520. The second depth T4′ may be determined, e.g., in the second chemical reinforcement process S50ofFIG.5. The second depth T4′ may have, e.g., a length of 5% to 20% of the second thickness T3′, but is not limited thereto.

According to an example, the second glass portion520may include recesses522aand522bformed in the upper side and the lower side. The recesses522aand522bmay include, e.g., a first recess522ain the second glass portion520toward the upper surface500aof the transparent member500and a second recess522bin the second glass portion520toward the lower surface500bof the transparent member500. In the second glass portion522, recesses522aand522bmay be formed in the upper and lower sides, thereby forming a top-bottom notch structure. According to an embodiment of the disclosure, stress may be dispersed by forming the recesses522aand522bin both the upper and lower sides of the second glass portion520.

According to an example, in the unfolding state of the transparent member500, the upper surface of the first glass portion510and the upper surface of the second glass portion520may be positioned on different planes. Due to the first recess522aformed in the upper side of the second glass portion520, the upper surface of the second glass portion520may not be included in the plane including the upper surface of the first glass portion510. For example, the upper surface of the second glass portion520may not be included in the plane including the upper surface of the first glass portion510. In other words, for example, the upper surface of the second glass portion520may not be on the same plane as the upper surface of the first glass portion510. Here, the upper surface of the first glass portion510may be the upper surface500aof the transparent member500. Here, the unfolding state of the transparent member500may refer to a state in which no bend exists in all areas of the transparent member500.

According to an example, in the unfolding state of the transparent member500, the lower surface of the first glass portion510and the lower surface of the second glass portion520may be positioned on different planes. Due to the second recess522bformed in the lower side of the second glass portion520, the lower surface of the second glass portion520may not be included in the plane including the lower surface of the first glass portion510. For example, the lower surface of the second glass portion520may not be included in the plane including the lower surface of the first glass portion510. In other words, for example, the lower surface of the second glass portion520may not be on the same plane as the lower surface of the first glass portion510. Here, the lower surface of the first glass portion510may be the lower surface500bof the transparent member500.

According to an example, the first depth T2′ and the second depth T4′ may be different in size. For example, the first depth T2′ may be greater than the second depth T4′. According to an example, the ratio of the first depth T2′ to the first thickness T1′ may be substantially the same as the ratio of the second depth T4′ to the second thickness T3′. For example, when the first thickness T1′ is 50 μm, and the second thickness T3′ is 30 μm, the first depth T2′ may be 7.5 μm, and the second depth may be 4.5 μm. By allowing the ratio of the first depth T2′ to the first thickness T1′ in the first glass portion510to be substantially the same as the ratio of the second depth T4′ to the second thickness T3′ in the second glass portion520, the difference in expansion rate between the first glass portion510and the second glass portion520may be minimized. By minimizing the difference in the expansion rate between the first glass portion510and the second glass portion520having the different thicknesses, it is possible to prevent warpage that may occur in the transparent member500(especially the second glass portion520).

According to an example, the second glass portion520may be formed to be horizontally symmetrical with respect to a virtual plane C′ that is perpendicular to the thickness direction of the transparent member500and passes through the transparent member. The virtual plane C′ may be, e.g., a plane perpendicular to the thickness direction of the transparent member500and dividing the average thickness of the transparent member500by half, but is not limited thereto. The virtual plane C′ may be, e.g., a plane perpendicular to the thickness direction of the transparent member500and dividing the average thickness of the first glass portion510by half, but is not limited thereto. Here, the thickness direction may refer to the Z2-axis direction. Alternatively, the thickness direction may refer to a direction from the lower surface500bof the transparent member500to the upper surface500aof the transparent member500. By forming the second glass portion520horizontally symmetrically with respect to the virtual plane C′, stress may be evenly dispersed to the first glass portions510positioned on two opposite sides of the second glass portion520.

According to an example, the boundary between the first glass portion510and the second glass portion520may have a surface/plane level difference (e.g., step or bump).

According to an example, although not illustrated, the transparent member500may further include a refractive index matching portion. For example, the refractive index matching portion may be disposed around at least one of the first glass portion510or the second glass portion520to match the refractive indexes of light formed by the difference in thickness between the first glass portion510and the second glass portion520. The refractive index matching portion may be formed of, e.g., a transparent material. The refractive index matching portion may be formed of, e.g., a urethane-based, acrylic-based, or silicon-based material. The refractive index matching portion may have substantially the same refractive index as that of a base layer501.

FIG.19is a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

Referring toFIG.19, a transparent member500-1may be a cross section of the transparent member500-1with respect to the cross section taken along line V4-V4′ of the flexible display (e.g., the flexible display430ofFIG.17B) ofFIG.17B. InFIG.19, the thickness of the first glass portion510, the first depth of the first area511, the thickness of the second glass portion520-1, and the second depth of the second area521-1have been described with reference toFIG.18, and are not described below. A detailed description of the components described with reference toFIG.18among the components ofFIG.19will be omitted. For convenience of description, the thickness of the transparent member500-1may be somewhat exaggerated inFIG.19.

The transparent member500-1according to an embodiment is entirely the same as or similar to the transparent member500ofFIG.18, but is different in that the transparent member300-1further includes a third portion530. The following description focuses primarily on the differences.

According to an example, the third portion530may be disposed between the first glass portion510and the second glass portion520-1. The third portion530may be disposed so that one side contacts an edge of the first glass portion510and the other side contacts an edge of the second glass portion520-1. The third portion530may have an inclined/declined slope. The third portion530may be formed to be inclined downward from, e.g., the first glass portion510toward the second glass portion520-1. The third portion530may be formed to be inclined to connect, e.g., the first glass portion510and the second glass portion520-1. The slope of the third portion530may be a flat slope, but is not limited thereto, and may be a curved slope.

According to an example, the third portion530may be formed by the etching process S30ofFIG.5. In the etching process S30, the upper recess522a-1and the lower recess522b-1may be formed around the second glass portion520-1and the third portion530. Accordingly, the chemical enhancement depth of the third portion530may be the same as or similar to the chemical enhancement depth of the second glass portion520-1.

By adding the third portion530to the boundary between the first glass portion510and the second glass portion520-1of the transparent member500-1, the thickness of the base layer501may be gradually changed to enhance visibility of the transparent member500-1.

FIG.20is a view illustrating an electronic device in a closed state according to an embodiment of the disclosure.FIG.21is a view illustrating an electronic device in an open state according to an embodiment of the disclosure.

An electronic device600ofFIGS.20and21may be at least partially similar to the electronic device101ofFIG.1and/or may include other embodiments of the electronic device101. Some of the components of the electronic device600illustrated inFIGS.20and21may be the same as or similar to some of the components of the electronic device400illustrated inFIGS.15A,15B,16A, and16B. Hereinafter, descriptions of duplicate configurations will be omitted.

Referring toFIGS.20and21, an electronic device600according to an embodiment may include all or some of a first housing610, a second housing620, a third housing630, and a flexible display640.

The second housing620and the third housing630may be symmetrical with respect to the center line of the first housing610, but are not limited thereto. Here, the center line of the first housing610may refer to a virtual line in the Z3-axis direction that divides the first housing in half.

The second housing620may be coupled to the first housing610to be movable in a designated direction and within a designated distance from the first housing610. For example, the designated direction may be the first direction D1. At least a portion of the second housing620may be received in the first housing610. The second housing620may slide relative to the first housing610while at least a portion of the second housing620is received in the first housing610.

The third housing630may be coupled to the first housing610to be movable in a designated direction and within a designated distance from the first housing610. For example, the designated direction may be the second direction D2. The second direction D2may be a direction opposite to the first direction D1, but is not limited thereto. Although not shown, the second direction may be a direction perpendicular to the first direction D1. At least a portion of the third housing630may be received in the first housing610. The third housing630may slide relative to the first housing610while at least a portion of the third housing630is received in the first housing610.

As the second housing620and/or the third housing630slides relative to the first housing610, the flexible display640may switch between an open state and a closed state. Here, the open state may refer to a state in which the area in which the flexible display640is exposed to the front surface of the electronic device600is maximized. Alternatively, the open state may refer to a state in which the second housing620and the third housing630are maximally slid out from the first housing610. Here, the closed state may refer to a state in which the area in which the flexible display640is exposed to the front surface of the electronic device600is minimized. Alternatively, the closed state may refer to a state in which the second housing620and the third housing630are maximally slid into the first housing610. The flexible display640may have an intermediate state between the open state and the closed state depending on the degree of exposure to the front surface of the electronic device600.

The flexible display640may be received across the first housing610, the second housing620, and the third housing. For example, the flexible display640may be disposed on the front surface of the electronic device600to be supported through at least a portion of the first housing610, the second housing620, and the third housing630.

For example, as the second housing620or the third housing630slides in a designated direction with respect to the first housing610, the display area of the flexible display640may vary. The second housing620and the third housing630may operate independently of each other. For example, the second housing620may slide relative to the first housing610regardless of the movement or position of the third housing630. For example, the third housing630may slide relative to the first housing610regardless of the movement or position of the second housing620. However, the disclosure is not limited thereto, and the second housing620and the third housing630may operate symmetrically with respect to the center line of the first housing610.

The flexible display640may include a first area640aand second areas640band640cextending from the first area640a. The first area640amay be an area in which a state of being exposed to the front surface of the electronic device600is maintained. The first area640amay be, e.g., a non-flexible area that maintains a flat surface in the flexible display640. The second areas640band640cmay be areas variably exposed to the front surface of the electronic device600according to the operating state of the electronic device600. For example, the second areas640band640cmay be flexible areas that may be bent. For example, in the closed state, only the first area640aof the flexible display640may be exposed to the front surface of the electronic device600. For example, in the open state, all of the first area640aand the second areas640band640cof the flexible display640may be exposed to the front surface of the electronic device600. The size of the second areas640band640cexposed to the front surface of the electronic device600may vary depending on the degree to which the second housing620and the third housing630slide out with respect to the first housing610.

The second areas640band640cof the flexible display640may include a 2-1tharea640band a 2-2tharea640c. The 2-1 area640band the 2-2 area640ceach may be disposed adjacent to the first area640a. For example, the 2-1tharea640bmay extend from one side (e.g., an edge in the −X3-axis direction) of the first area640a. For example, the 2-2tharea640cmay extend from another side (e.g., an edge in the +X3-axis direction) of the first area640a.

FIGS.22A and22Bare perspective views illustrating a flexible display according to various embodiments of the disclosure.

Referring toFIGS.22A and22B, the flexible display640may include a first area640aand second areas640band640cextending from the first area640a.

The flexible display640may include a display panel and a transparent member (e.g., a transparent member700ofFIG.23or the transparent member700-1ofFIG.24). Like the flexible display640, the display panel may include a flexible area (e.g., the second areas630band640c) and a non-flexible area (e.g., the first area640a) adjacent to the flexible area.

The display panel may be provided to display an image. The display panel may be, e.g., a light emitting display panel, but is not limited thereto. The display panel may be, e.g., an organic light emitting display panel or a quantum dot light emitting display panel. The light emitting layer of the organic light emitting display panel may include an organic light emitting material. The light emitting layer of the quantum dot light emitting display panel may include quantum dots and quantum rods. The display panel may be flexible.

The transparent member700(or window) may be disposed on, e.g., the display panel. Different components (e.g., input detection units) may be disposed on the transparent member700and the display panel. The transparent member700may include an optically transparent insulating material. Accordingly, the image generated by the display panel may be easily transferred to the user through the transparent member700.

The transparent member700may transmit the image from the display panel while mitigating the external impact, thereby preventing the display panel from being damaged or malfunctioning due to the external impact. Here, the external impact is a force applied from the outside, such as pressure and stress, and may refer to a force that causes damage to the display panel.

FIG.23is a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

Referring toFIG.23, the transparent member700may be a cross section of the transparent member700with respect to the cross section taken along line V5-V5′ of the flexible display (e.g., the flexible display640ofFIG.22B) ofFIG.22B. For convenience of description, the thickness of the transparent member700may be somewhat exaggerated inFIG.23.

The transparent member700may include a first glass portion710and second glass portions720aand720b. The first glass portion710may extend from one edge of the second glass portion720aand720b. The second glass portion720aand720bmay be disposed, e.g., between two first glass portions710. A 2-1th portion720amay be disposed on one side of one first glass portion710, and a 2-2th portion720bmay be disposed on the other side of the first glass portion710.

According to an example, the first glass portion710may correspond to a non-flexible area of the flexible display640or a display panel (not shown). The first glass portion710may have a first thickness T1″. Here, the first thickness T1″ may refer to a length between an upper surface700aand a lower surface700bof the transparent member700in the first glass portion710. Alternatively, the first thickness T1″ may refer to the length of the first glass portion710in the Z3-axis direction. The first thickness T1″ may be larger than, e.g., the second thickness T3″. The first thickness T1″ may be, e.g., 50 μm to 500 μm, but is not limited thereto.

According to an example, the first glass portion710may include a first area711. The first area711may have a first depth T2″. Here, the first depth T2″ may refer to the length of the chemically reinforced area from the surface of the first glass portion710. The first depth T2″ may be determined, e.g., in the first chemical reinforcement process S20ofFIG.5. The first depth T2″ may have, e.g., a length of 5% to 20% of the first thickness T1″, but is not limited thereto.

According to an example, the second glass portion720aand720bmay correspond to a flexible area of the flexible display640or a display panel (not shown). The second glass portion720aand720bmay have a second thickness T3″. Here, the second thickness T3″ may refer to a length between the upper surface700aand the lower surface700bof the transparent member700in the second glass portion720aand720b. Alternatively, the second thickness T3″ may refer to the length of the second glass portion720aand720bin the Z3-axis direction. The second thickness T3″ may be smaller than, e.g., the first thickness T1″. The second thickness T3″ may be, e.g., 30 μm to 50 μm, but is not limited thereto.

According to an example, the second glass portion720aand720bmay include a second area721. The second area721may have a second depth T4″ different from the first depth T2″. Here, the second depth T4″ may refer to the length of the chemically reinforced area from the surface of the second glass portion720aand720b. The second depth T4″ may be determined, e.g., in the second chemical reinforcement process S50ofFIG.5. The second depth T4″ may have, e.g., a length of 5% to 20% of the second thickness T3″, but is not limited thereto.

According to an example, the second glass portion720aand720bmay include recesses722aand722bformed in the upper side and the lower side. The recesses722aand722bmay include, e.g., a first recess722ain the second glass portion720aand720btoward the upper surface700aof the transparent member700and a second recess722bin the second glass portion720aand720btoward the lower surface700bof the transparent member700. According to an embodiment of the disclosure, internal stress of the first glass portion710may be dispersed by forming the recesses722aand722bin both the upper and lower sides of the second glass portion720aand720b.

According to an example, in the unfolding state of the transparent member700, the upper surface of the first glass portion710and the upper surface of the second glass portion720aand720bmay be positioned on different planes. Due to the first recess722aformed in the upper side of the second glass portion720aand720b, the upper surface of the second glass portion720aand720bmay not be included in the plane including the upper surface of the first glass portion710. For example, the upper surface of the second glass portion720aand720bmay not be included in the plane including the upper surface of the first glass portion710. In other words, for example, the upper surface of the second glass portion720aand720bmay not be on the same plane as the upper surface of the first glass portion710. Here, the upper surface of the first glass portion710may be the upper surface700aof the transparent member700. Here, the unfolding state of the transparent member700may refer to a state in which no bend exists in all areas of the transparent member700.

According to an example, in the unfolding state of the transparent member700, the lower surface of the first glass portion710and the lower surface of the second glass portion720aand720bmay be positioned on different planes. Due to the second recess722bformed in the lower side of the second glass portion720aand720b, the lower surface of the second glass portion720aand720bmay not be included in the plane including the lower surface of the first glass portion710. For example, the lower surface of the second glass portion720aand720bmay not be included in the plane including the lower surface of the first glass portion710. In other words, for example, the lower surface of the second glass portion720aand720bmay not be on the same plane as the lower surface of the first glass portion510. Here, the lower surface of the first glass portion710may be the lower surface700bof the transparent member700.

According to an example, the first depth T2″ and the second depth T4″ may be different in size. For example, the first depth T2″ may be greater than the second depth T4″. According to an example, the ratio of the first depth T2″ to the first thickness T1″ may be substantially the same as the ratio of the second depth T4″ to the second thickness T3″. For example, when the first thickness T1″ is 50 μm, and the second thickness T3″ is 30 μm, the first depth T2″ may be 7.5 μm, and the second depth may be 4.5 μm. By allowing the ratio of the first depth T2″ to the first thickness T1″ in the first glass portion710to be substantially the same as the ratio of the second depth T4″ to the second thickness T3″ in the second glass portion720aand720b, the difference in expansion rate between the first glass portion710and the second glass portion720aand720bmay be minimized. By minimizing the difference in the expansion rate between the first glass portion710and the second glass portion720aand720bhaving the different thicknesses, it is possible to prevent warpage that may occur in the transparent member700(especially the second glass portion720aand720b).

According to an example, the second glass portion720aand720bmay be formed to be horizontally symmetrical with respect to a virtual plane C″ that is perpendicular to the thickness direction of the transparent member700and passes through the transparent member. The virtual plane C″ may be, e.g., a plane perpendicular to the thickness direction of the transparent member700and dividing the average thickness of the transparent member700by half, but is not limited thereto. The virtual plane C″ may be, e.g., a plane perpendicular to the thickness direction of the transparent member700and dividing the average thickness of the first glass portion710by half, but is not limited thereto. Here, the thickness direction may refer to the Z3-axis direction. Alternatively, the thickness direction may refer to a direction from the lower surface700bof the transparent member700to the upper surface700aof the transparent member700. By forming the second glass portion720aand720bhorizontally symmetrically with respect to the virtual plane C″, stress may be evenly dispersed to the first glass portions710positioned on two opposite sides of the second glass portion720aand720b.

According to an example, the boundary between the first glass portion710and the second glass portion720aand720bmay have a surface/plane level difference (e.g., step or bump).

According to an example, although not illustrated, the transparent member700may further include a refractive index matching portion. For example, the refractive index matching portion may be disposed around at least one of the first glass portion710or the second glass portion720aand720bto match the refractive indexes of light formed by the difference in thickness between the first glass portion710and the second glass portion720aand720b. The refractive index matching portion may be formed of, e.g., a transparent material. The refractive index matching portion may be formed of, e.g., a urethane-based, acrylic-based, or silicon-based material. The refractive index matching portion may have substantially the same refractive index as that of the base layer701.

FIG.24is a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

Referring toFIG.24, the transparent member700-1may be a cross section of the transparent member700-1with respect to the cross section taken along line V5-V5′ of the flexible display (e.g., the flexible display640ofFIG.22B) ofFIG.22B. InFIG.24, the thickness of the first glass portion710, the first depth of the first area711, the thickness of the second glass portion720a-1and720b-1, and the second depth of the second area721-1have been described with reference toFIG.23, and are not described below. A detailed description of the components described with reference toFIG.23among the components ofFIG.24will be omitted. For convenience of description, the thickness of the transparent member700-1may be somewhat exaggerated inFIG.24.

The transparent member700-1according to an embodiment is entirely the same as or similar to the transparent member700ofFIG.23, but is different in that the transparent member700-1further includes a third portion730aand730b. The following description focuses primarily on the differences.

According to an example, the third portion730aand730bmay be disposed between the first glass portion710and the second glass portion720a-1and720b-1. The third portion730aand730bmay be disposed so that one side contacts an edge of the first glass portion710and the other side contacts an edge of the second glass portion720a-1and720b-1. The third portion730aand730bmay have an inclined/declined slope. The third portion730aand730bmay be formed to be inclined downward from, e.g., the first glass portion710toward the second glass portion720a-1and720b-1. The third portion730aand730bmay be formed to be inclined to connect, e.g., the first glass portion710and the second glass portion720a-1and720b-1. The slope of the third portion730aand730bmay be a flat slope, but is not limited thereto, and may be a curved slope.

According to an example, the third portion730aand730bmay be formed by the etching process S30ofFIG.5. In the etching process S30, the upper recess722a-1and the lower recess722b-1may be formed around the second glass portion720a-1and720b-1and the third portion730aand730b. Accordingly, the chemical enhancement depth of the third portion730aand730bmay be the same as or similar to the chemical enhancement depth of the second glass portion720a-1and720b-1.

By adding the third portion730aand730bto the boundary between the first glass portion710and the second glass portion720a-1and720b-1of the transparent member700-1, the thickness of the base layer701may be gradually changed to enhance visibility of the transparent member700-1.

FIG.25is a view illustrating an electronic device in a closed state according to an embodiment of the disclosure.FIG.26is a view illustrating an electronic device in an open state according to an embodiment of the disclosure.

An electronic device800ofFIGS.25and26may be at least partially similar to the electronic device101ofFIG.1or may include other embodiments of the electronic device101.

Referring toFIGS.25and26, an electronic device800according to an embodiment may include a housing810, a flexible display840, and a roller member830. For example, at least a portion of the flexible display840and the roller member830may be received in the housing810. The electronic device800may be disposed inside the housing810in a state in which the flexible display840is rolled around the roller member830. The flexible display840may have a structure that provides a display area in which a screen is displayed by being pulled out of the housing810and unfolded by the user's manipulation or a mechanical operation of the roller member830.

An opening (not shown) may be formed on one side of the housing810to allow the flexible display840to move. The flexible display840may be exposed by moving to the outside of the housing810through an opening or may be received in the housing810. The roller member830may be rotatably coupled to the housing810. The roller member830may be surrounded by at least a portion of the flexible display840. As the roller member830rotates relative to the housing810inside the housing810, the flexible display840may move outward or inward of the housing810.

The flexible display840may be wound or wrapped around the roller member830. One end of the flexible display840may be connected to the roller member830. The flexible display840may be directly connected to, e.g., the roller member830, or may be indirectly connected to the roller member830through a medium (not shown) for transferring a signal.

The flexible display840may include a first area840aand a second area840bextending from the first area840a. The first area840amay be, e.g., a non-flexible area that maintains a flat surface in the flexible display840. The second area840bmay be, e.g., a flexible area that may be bent. An area of the second area840bexposed to the outside may vary as the roller member830rotates.

The flexible display840may switch between an open state and a closed state as the roller member830rotates. Here, the open state may refer to a state in which an area in which the flexible display840rolled or wrapped around the roller member830is exposed to the outside of the housing810is maximized by rotation of the roller member830. Here, the closed state may refer to a state in which the flexible display840is maximally rolled around the roller member830. The flexible display840may have an intermediate state between the open state and the closed state depending on the degree to which the flexible display840is exposed to the outside of the housing810.

In the closed state of the flexible display840, the first area840amay be exposed to the outside. However, the disclosure is not limited thereto, and all areas of the flexible display840may not be exposed to the outside in the closed state of the flexible display840.

The flexible display840may include a display panel and a transparent member (e.g., a transparent member900ofFIG.27or the transparent member900-1ofFIG.28).

The display panel may be provided to display an image. The display panel may be, e.g., a light emitting display panel, but is not limited thereto. The display panel may be, e.g., an organic light emitting display panel or a quantum dot light emitting display panel. The light emitting layer of the organic light emitting display panel may include an organic light emitting material. The light emitting layer of the quantum dot light emitting display panel may include quantum dots and quantum rods. The display panel may be flexible.

The transparent member900(or window) may be disposed on, e.g., the display panel. Different components (e.g., input detection units) may be disposed on the transparent member900and the display panel. The transparent member900may include an optically transparent insulating material. Accordingly, the image generated by the display panel may be easily transferred to the user through the transparent member900.

The transparent member900may transmit the image from the display panel while mitigating the external impact, thereby preventing the display panel from being damaged or malfunctioning due to the external impact. Here, the external impact is a force applied from the outside, such as pressure and stress, and may refer to a force that causes damage to the display panel.

FIG.27is a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

For convenience of description, the thickness of the transparent member900may be somewhat exaggerated inFIG.27.

Referring toFIG.27, the transparent member900may include a first glass portion910and a second glass portion920. The first glass portion910may extend from one edge of the second glass portion920.

According to an example, the first glass portion910may correspond to a non-flexible area of the flexible display840or a display panel (not shown). The first glass portion910may have a first thickness T1′″. Here, the first thickness T1′″ may refer to a length between an upper surface900aand a lower surface900bof the transparent member900in the first glass portion910. Alternatively, the first thickness T1′″ may refer to the length of the first glass portion910in the Z4-axis direction. The first thickness T1′″ may be larger than, e.g., the second thickness T3′″. The first thickness T1′″ may be, e.g., 50 μm to 500 μm, but is not limited thereto.

According to an example, the first glass portion910may include a first area911. The first area911may have a first depth T2′″. Here, the first depth T2′″ may refer to the length of the chemically reinforced area from the surface of the first glass portion910. The first depth T2′″ may be determined, e.g., in the first chemical reinforcement operation S20ofFIG.5. The first depth T2′″ may have, e.g., a length of 5% to 20% of the first thickness T1′″, but is not limited thereto.

According to an example, the second glass portion920may correspond to a flexible area of the flexible display840or a display panel (not shown). The second glass portion920may have a second thickness T1′″. Here, the second thickness T1′″ may refer to a length between the upper surface900aand the lower surface900bof the transparent member900in the second glass portion920. Alternatively, the second thickness T1′″ may refer to the length of the second glass portion920in the Z4-axis direction. The second thickness T3′″ may be smaller than, e.g., the first thickness T1′″. The second thickness T1′″ may be, e.g., 30 μm to 60 μm, but is not limited thereto.

According to an example, the second glass portion920may include a second area921. The second area921may have a second depth T4′″ different from the first depth T2′″. Here, the second depth T4′″ may refer to the length of the chemically reinforced area from the surface of the second glass portion920. The second depth T4′″ may be determined, e.g., in the second chemical reinforcement process S50ofFIG.5. The second depth T4′″ may have, e.g., a length of 5% to 20% of the second thickness T3′″, but is not limited thereto.

According to an example, the second glass portion920may include recesses922aand922bformed in the upper side and the lower side. The recesses922aand922bmay include, e.g., a first recess922ain the second glass portion920toward the upper surface900aof the transparent member900and a second recess922bin the second glass portion920toward the lower surface900bof the transparent member900. In the second glass portion922, recesses922aand922bmay be formed in the upper and lower sides, thereby forming a top-bottom notch structure. According to an embodiment of the disclosure, stress may be dispersed by forming the recesses922aand922bin both the upper and lower sides of the second glass portion920.

According to an example, in the unfolding state of the transparent member900, the upper surface of the first glass portion910and the upper surface of the second glass portion920may be positioned on different planes. Due to the first recess922aformed in the upper side of the second glass portion920, the upper surface of the second glass portion920may not be included in the plane including the upper surface of the first glass portion910. For example, the upper surface of the second glass portion920may not be included in the plane including the upper surface of the first glass portion910. In other words, for example, the upper surface of the second glass portion920may not be on the same plane as the upper surface of the first glass portion910. Here, the upper surface of the first glass portion910may be the upper surface900aof the transparent member900. Here, the unfolding state of the transparent member900may refer to a state in which no bend exists in all areas of the transparent member900.

According to an example, in the unfolding state of the transparent member900, the lower surface of the first glass portion910and the lower surface of the second glass portion920may be positioned on different planes. Due to the second recess922bformed in the lower side of the second glass portion920, the lower surface of the second glass portion920may not be included in the plane including the lower surface of the first glass portion910. For example, the lower surface of the second glass portion920may not be included in the plane including the lower surface of the first glass portion910. In other words, for example, the upper surface of the second glass portion920may not be on the same plane as the upper surface of the first glass portion910. Here, the lower surface of the first glass portion910may be the lower surface900bof the transparent member900.

According to an example, the first depth T2′″ and the second depth T4′″ may be different in size. For example, the first depth T2′″ may be greater than the second depth T4′″. According to an example, the ratio of the first depth T2′″ to the first thickness T1′″ may be substantially the same as the ratio of the second depth T4′″ to the second thickness T3′″. For example, when the first thickness T1′″ is 50 μm, and the second thickness T3′″ is 30 μm, the first depth T2′″ may be 7.5 μm, and the second depth may be 4.5 μm. By allowing the ratio of the first depth T2′″ to the first thickness T1′″ in the first glass portion910to be substantially the same as the ratio of the second depth T4′″ to the second thickness T3′″ in the second glass portion920, the difference in expansion rate between the first glass portion910and the second glass portion920may be minimized. By minimizing the difference in the expansion rate between the first glass portion910and the second glass portion920having the different thicknesses, it is possible to prevent warpage that may occur in the transparent member900(especially the second glass portion920).

According to an example, the second glass portion920may be formed to be horizontally symmetrical with respect to a virtual plane C′″ that is perpendicular to the thickness direction of the transparent member900and passes through the transparent member. The virtual plane C′″ may be, e.g., a plane perpendicular to the thickness direction of the transparent member900and dividing the average thickness of the transparent member900by half, but is not limited thereto. The virtual plane C′″ may be, e.g., a plane perpendicular to the thickness direction of the transparent member900and dividing the average thickness of the first glass portion910by half, but is not limited thereto. Here, the thickness direction may refer to the Z4-axis direction. Alternatively, the thickness direction may refer to a direction from the lower surface900bof the transparent member900to the upper surface900aof the transparent member900. By forming the second glass portion920horizontally symmetrically with respect to the virtual plane C′″, stress may be evenly dispersed to the first glass portions910positioned on two opposite sides of the second glass portion920.

According to an example, the boundary between the first glass portion910and the second glass portion920may have a surface/plane level difference (e.g., step or bump).

According to an example, although not illustrated, the transparent member900may further include a refractive index matching portion. For example, the refractive index matching portion may be disposed around at least one of the first glass portion910or the second glass portion920to match the refractive indexes of light formed by the difference in thickness between the first glass portion910and the second glass portion920. The refractive index matching portion may be formed of, e.g., a transparent material. The refractive index matching portion may be formed of, e.g., a urethane-based, acrylic-based, or silicon-based material. The refractive index matching portion may have substantially the same refractive index as that of a base layer901.

FIG.28is a cross-sectional view illustrating a transparent member according to an embodiment of the disclosure.

Referring toFIG.28, the thickness of the first glass portion910, the first depth of the first area911, the thickness of the second glass portion920-1, and the second depth of the second area921-1have been described with reference toFIG.27, and are not described below. A detailed description of the components described with reference toFIG.27among the components ofFIG.28will be omitted. For convenience of description, the thickness of the transparent member900-1may be somewhat exaggerated inFIG.28.

The transparent member900-1according to an embodiment is entirely the same as or similar to the transparent member900ofFIG.27, but is different in that the transparent member300-1further includes a third portion930. The following description focuses primarily on the differences.

According to an example, the third portion930may be disposed between the first glass portion910and the second glass portion920-1. The third portion930may be disposed so that one side contacts an edge of the first glass portion910and the other side contacts an edge of the second glass portion920-1. The third portion930may have an inclined/declined slope. The third portion930may be formed to be inclined downward from, e.g., the first glass portion910toward the second glass portion920-1. The third portion930may be formed to be inclined to connect, e.g., the first glass portion910and the second glass portion920-1. The slope of the third portion930may be a flat slope, but is not limited thereto, and may be a curved slope.

According to an example, the third portion930may be formed by the etching process S30ofFIG.5. In the etching process S30, the upper recess922a-1and the lower recess922b-1may be formed around the second glass portion920-1and the third portion930. Accordingly, the chemical enhancement depth of the third portion930may be the same as or similar to the chemical enhancement depth of the second glass portion920-1.

By adding the third portion930to the boundary between the first glass portion910and the second glass portion920-1of the transparent member900-1, the thickness of the base layer901may be gradually changed to enhance visibility of the transparent member900-1.

FIGS.29and30are tables illustrating a difference in expansion length of a transparent member with different thicknesses according to a chemical reinforcement depth proportion according to various embodiments of the disclosure.

FIG.29is an experimental example for describing an expansion length difference (mm) that occurs when all areas of a transparent member having differential thicknesses are formed to have the same reinforcement depth, according to an embodiment of the disclosure. Hereinafter, in the description ofFIG.29, the first glass portion of the transparent member may refer to a portion corresponding to the non-flexible area of the flexible display, and the second glass portion of the transparent member may refer to a portion corresponding to the flexible area of the flexible display.

Referring toFIG.29, when all surfaces of the transparent member having the differential thickness are reinforced based on the reinforcement depth proportion of the first glass portion, there may be a difference in expansion length between the first glass portion and the second glass portion.

For example, if the reinforcement depths of the first glass portion and the second glass portions are formed to be the same as, e.g., 5 μm when the thickness of the first glass portion is 50 μm, and the thickness of the second glass portion is 30 μm, the reinforcement depth proportion of the first glass portion may be 10.0%, and the reinforcement depth proportion may be 16.7%. As the reinforcement depth proportions differ, a difference may occur in the expansion rate (0.09%) of the first glass portion and the expansion rate (0.14%) of the second glass portion. Depending on the difference in expansion rate, the difference in expansion length between the first glass portion and the second glass portion may be 0.06 mm, which may result in warpage.

For example, if the reinforcement depths of the first glass portion and the second glass portions are formed to be the same as, e.g., 8 μm when the thickness of the first glass portion is 80 μm, and the thickness of the second glass portion is 40 μm, the reinforcement depth proportion of the first glass portion may be 10.0%, and the reinforcement depth proportion may be 20%. As the reinforcement depth proportions differ, a difference may occur in the expansion rate (0.09%) of the first glass portion and the expansion rate (0.17%) of the second glass portion. Depending on the difference in expansion rate, the difference in expansion length between the first glass portion and the second glass portion may be 0.09 mm, which may result in warpage.

Referring toFIG.29, when all surfaces of the transparent member having the differential thickness are reinforced based on the reinforcement depth proportion of the second glass portion, there may be a difference in expansion length between the first glass portion and the second glass portion.

For example, if the reinforcement depths of the first glass portion and the second glass portions are formed to be the same as, e.g., 4.5 μm when the thickness of the first glass portion is 50 μm, and the thickness of the second glass portion is 30 μm, the reinforcement depth proportion of the first glass portion may be 9.0%, and the reinforcement depth proportion may be 15%. As the reinforcement depth proportions differ, a difference may occur in the expansion rate (0.08%) of the first glass portion and the expansion rate (0.13%) of the second glass portion. Depending on the difference in expansion rate, the difference in expansion length between the first glass portion and the second glass portion may be 0.05 mm, which may result in warpage.

For example, if the reinforcement depths of the first glass portion and the second glass portions are formed to be the same as, e.g., 6 μm when the thickness of the first glass portion is 80 μm, and the thickness of the second glass portion is 40 μm, the reinforcement depth proportion of the first glass portion may be 7.5%, and the reinforcement depth proportion may be 15%. As the reinforcement depth proportions differ, a difference may occur in the expansion rate (0.06%) of the first glass portion and the expansion rate (0.13%) of the second glass portion. Depending on the difference in expansion rate, the difference in expansion length between the first glass portion and the second glass portion may be 0.06 mm, which may result in warpage.

FIG.30is an experimental example for describing that there is no difference in expansion length between the first glass portion and the second glass portion when the first depth and the second depth are formed to have the same reinforcement depth proportion according to an embodiment of the disclosure. The table ofFIG.30is illustrative and does not limit the scope of the disclosure.

Referring toFIG.30, according to various embodiments of the disclosure, it is possible to minimize the difference in expansion length by matching the reinforcement depth proportions by making the first depth T2, T2′, T2″, or T2′″ of the first area311,511,711, or911different from the second depth T4, T4′, T4″, or T4′″ of the second area321,521,721, and921regardless of the first thickness T1, T1′, T1″, or T1′″ of the first glass portion310,510,710, or910and the second thickness T3, T3′, T2″, or T3′″ of the second glass portion320,520,720, or920.

For example, the transparent member300,500,700, or900according to an embodiment may be implemented so that the reinforcement depth proportions of all areas of the transparent member300,500,700, or900are 15% regardless of the first thickness T1, T1′, T1″, and T1′″ of the first glass portion310,510,710, or910and the second thickness T3, T3′, T3″, or T3′″ of the second glass portion320,520,720, or920. It is possible to minimize the difference in expansion length by matching the reinforcement depth proportion in the first glass portion310,510,710, or910with the reinforcement depth proportion in the second glass portion320,520,720, or920. As a result, it is possible to prevent the transparent member300,500,700, or900having different thicknesses from being twisted.

The flexible transparent member300,500,700, or900according to an embodiment may include a first glass portion310,510,710, or910having a first thickness T1, T1′, T1″, or T1′″, a second glass portion320,520,720, or920having a second thickness T3, T3′, T3″, or T3′″ thinner than the first thickness T1, T1′, T1″, or T1′″, and a resin portion disposed on the second glass portion320,520,720, or920. An upper surface of the second glass portion may be recessed in a downward direction with respect to an upper surface of the first glass portion. A lower surface of the second glass portion may be recessed in an upward direction with respect to a lower surface of the first glass portion. The resin portion may be filled in the recessed region.

According to an embodiment of the disclosure, the first glass portion310,510,710, or910and the second glass portion320,520,720, or920may be formed to be horizontally symmetrical.

According to an embodiment of the disclosure, the first glass portion310,510,710, or910may include a first area311,511,711, or911chemically reinforced inward from a surface by a first depth T2, T2′, T2″, or T2′″. The second glass portion320,520,720, or920may include a second area321,521,721, or921chemically reinforced inward from a surface by a second depth T4, T4′, T4″, or T4′″ different from the first depth T2, T2′, T2″, or T2′″.

According to an embodiment of the disclosure, a ratio of the first depth T2, T2′, T2″, or T2′″ to the first thickness T1, T1′, T1″, or T1′″ may be substantially the same as a ratio of the second enhancement depth T4, T4′, T4″, or T4′″ to the second thickness T3, T3′, T3″, or T3′″.

According to an embodiment of the disclosure, a flexible display may comprise a display panel and a transparent member300,500,700, or900disposed on the display panel. The transparent member300,500,700, or900may include a first glass portion310,510,710, or910having a first thickness T1, T1′, T1″, or T1′″ and a second glass portion320,520,720, or920having a second thickness T3, T3′, T3″, or T3′″ smaller than the first thickness T1, T1′, T1″, or T1′″. An upper surface of the second glass portion320,520,720, or920may be recessed in a direction toward the display panel with respect to an upper surface of the first glass portion310,510,710, or910. A lower surface of the second glass portion320,520,720, or920may be recessed in an opposite direction to the display panel with respect to a lower surface of the first glass portion310,510,710, or910.

According to an embodiment of the disclosure, the first glass portion310,510,710, or910may include a first area311,511,711, or911chemically reinforced inward from a surface by a first depth T2, T2′, T2″, or T2′″. The second glass portion320,520,720, or920may include a second area321,521,721, or921chemically reinforced inward from a surface by a second depth T4, T4′, T4″, or T4′″.

According to an embodiment of the disclosure, the first depth T2, T2′, T2″, or T2′″ may be longer than the second depth T4, T4′, T4″, or T4′″.

According to an embodiment of the disclosure, a ratio of the first depth T2, T2′, T2″, or T2′″ to the first thickness T1, T1′, T1″, or T1′″ may be substantially same as a ratio of the second depth T4, T4′, T4″, or T4′″ to the second thickness T3, T3′, T3″, or T3′″.

According to an embodiment of the disclosure, the first depth T2, T2′, T2″, or T2′″ may have a length of 5% to 20% of the first thickness T1, T1′, T1″, or T1′″. The second depth T4, T4′, T4″, or T4′″ may have a length of 5% to 20% of the second thickness T3, T3′, T3″, or T3′″.

According to an embodiment of the disclosure, the second glass portion320,520,720, or920may have a stepped shape with respect to the first glass portion310,510,710, or910.

According to an embodiment of the disclosure, the transparent member300,500,700, or900may include a third glass portion330,530,730, or930formed to be sloped to connect the first glass portion310,510,710, or910and the second glass portion320,520,720, or920.

According to an embodiment of the disclosure, the second glass portion320,520,720, or920may have a penetrated portion.

According to an embodiment of the disclosure, at least one of an upper surface or a lower surface of the second glass portion320,520,720, or920may have a pattern in which a concave portion324or326and a convex portion323or325are alternately disposed.

According to an embodiment of the disclosure, a boundary between the concave portion324and the convex portion323may be formed by a vertical step.

According to an embodiment of the disclosure, alternating pattern of the concave portion326and the convex portion325has a wave-shaped cross section.

According to an embodiment of the disclosure, the second glass portion320,520,720or920may be formed to be symmetrical with respect to a virtual plane that divides a thickness of the transparent member300,500,700or900in half.

According to an embodiment of the disclosure, the first depth T2, T2′, T2″, or T2′″ may have a length of 5% to 20% of the first thickness T1, T1′, T1″, or T1′″. The second depth T4, T4′, T4″, or T4′″ may have a length of 5% to 20% of the second thickness T3, T3′, T3″, or T3′″.

An electronic device according to an embodiment of the disclosure may comprise a housing including a first housing and a second housing, a hinge module connected with the first housing and the second housing, and a flexible display at least partially received in the first housing and the second housing. The flexible display may include a display panel and a transparent member300,500,700, or900arranged on the display panel. The transparent member300,500,700, or900may include a first glass portion310,510,710, or910having a first thickness T1, T1′, T1″, or T1′″ and a second glass portion320,520,720, or920having a second thickness T3, T3′, T3″, or T3′″ thinner than the first thickness T1, T1′, T1″, or T1′″. An upper surface of the second glass portion320,520,720, or920may be recessed in a direction toward the display panel with respect to an upper surface of the first glass portion310,510,710, or910. A lower surface of the second glass portion320,520,720, or920may be recessed in an opposite direction to the display panel with respect to a lower surface of the first glass portion310,510,710, or910.

According to an embodiment of the disclosure, the second glass portion320,520,720, or920may be formed to be symmetrical with respect to a virtual plane that divides a thickness of the transparent member300,500,700or900in half.

According to an embodiment of the disclosure, the first glass portion310,510,710, or910may include a first area311,511,711, or911chemically reinforced inward from a surface by a first depth T2, T2′, T2″, or T2′″. The second glass portion320,520,720, or920may include a second area321,521,721, or921chemically reinforced inward from a surface by a second depth T4, T4′, T4″, or T4′″ different from the first depth T2, T2′, T2″, or T2′″.

According to an embodiment of the disclosure, a ratio of the first depth T2, T2′, T2″, or T2′″ to the first thickness T1, T1′, T1″, or T1′″ may be substantially the same as a ratio of the second enhancement depth T4, T4′, T4″, or T4′″ to the second thickness T3, T3′, T3″, or T3′″.

According to an embodiment of the disclosure, a flexible display may comprise a display panel and a transparent member300,500,700, or900disposed on the display panel. The transparent member300,500,700, or900may include a first glass portion310,510,710or910of a first thickness T1, T1′, T1″, or T1′″ having a first area311,511,711, or911of a first depth T2, T2′, T2″, or T2′″ from a surface. The transparent member300,500,700, or900may include a second glass portion320,520,720, or910of a second thickness T3, T3′, T3″, or T3′″ thinner than the first thickness T1, T1′, T1″, or T1′″ having a second area321,521,721, or921of a second depth T4, T4′, T4″, or T4′″ smaller than the first depth T2, T2′, T2″, or T2′″.

A method of manufacturing a transparent member according to an embodiment comprises chemically strengthening an entire surface of a glass for a first time, etching a portion of the glass that has been chemically strengthened for a first period, and chemically strengthening the entire surface of the partially etched glass for a second period shorter than the first period.

The terms as used herein are provided merely to describe some embodiments thereof, but are not intended to limit the disclosure. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, each of such phrases as “A or B,” “at least one of A and B,” “at least one of A or B,” “A, B, or C,” “at least one of A, B, and C,” and “at least one of A, B, or C,” may include all possible combinations of the items enumerated together in a corresponding one of the phrases. As used herein, the term ‘and/or’ should be understood as encompassing any and all possible combinations by one or more of the enumerated items. As used herein, the terms “include,” “have,” and “comprise” are used merely to designate the presence of the feature, component, part, or a combination thereof described herein, but use of the term does not exclude the likelihood of presence or adding one or more other features, components, parts, or combinations thereof. As used herein, the terms “first” and “second” may modify various components regardless of importance and/or order and are used to distinguish a component from another without limiting the components.

As used herein, the terms “configured to” may be interchangeably used with the terms “suitable for,” “having the capacity to,” “designed to,” “adapted to,” “made to,” or “capable of” depending on circumstances. The term “configured to” does not essentially mean “specifically designed in hardware to.” Rather, the term “configured to” may mean that a device can perform an operation together with another device or parts. For example, a ‘device configured (or set) to perform A, B, and C’ may be a dedicated device to perform the corresponding operation or may mean a general-purpose device capable of various operations including the corresponding operation.

Meanwhile, the terms “upper side”, “lower side”, and “front and rear directions” used in the disclosure are defined with respect to the drawings, and the shape and position of each component are not limited by these terms.