KR20220096090A - Display apparatus - Google Patents

Abstract

According to an embodiment of the present specification, a display device comprises: cover glass formed in a dome shape; and a display module including a display panel and a back plate sequentially coupled to a lower surface of the cover glass. The cover glass has a pressure concentration unit corresponding to an area where pressure is concentrated on the display panel when the display panel and the back plate are bonded. The back plate has a first groove unit corresponding to the pressure concentration unit of the cover glass.

Description

display device {DISPLAY APPARATUS}

The present invention relates to a display device in which a non-uniformity of stress or pressure generated in a display module when a cover glass and a display module are bonded to each other is improved.

Recently, as we enter the information age, the field of display that visually expresses electrical information signals has developed rapidly, and in response to this, various display devices with excellent performance such as thinness, light weight, and low power consumption (Display Apparatus) have been developed. is being developed

Specific examples of the display device include a Liquid Crystal Display Apparatus (LCD), an Organic Light Emitting Display Apparatus (OLED), and a Quantum Dot Display Apparatus.

Such a display device is expanding its scope not only to TVs and mobile devices, but also to wearable devices such as smart watches.

In particular, the cover glass of a display device applied to a smart watch has various shapes that are different from the rectangular shape applied to a typical mobile terminal.

For example, a conventional display device is applied to a smart watch and wirelessly interlocked with a mobile terminal to provide various additional functions to the user.

The display device includes a display module seated inside a case formed in a predetermined shape, and a cover glass in close contact with an upper surface of the display module.

The display module has a flat top surface and is coupled to each other through bonding with the cover glass. Recently, in order to improve the user's visual visibility, the cover glass has been manufactured in a dome type convexly protruding upward.

When the display module is bonded to the dome-shaped cover glass, the stress according to the bonding is unevenly distributed at the edge position extending roundly to the upper side of the cover glass, and at a specific position, the stress or strain is As the concentration increases, the problem of strength decrease due to stress imbalance occurred.

In addition, after bonding the display module, bubbles are generated around the location where the stress is non-uniformly distributed, or the frequency of defects due to wrinkles increases, so countermeasures are required.

An object of the present specification is to propose a structure for reducing damage to a display device in which stress and pressure uniformity of a display module bonded to a cover glass are improved.

The tasks of the present specification are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the following description.

A display device according to an embodiment of the present specification includes a cover glass formed in a dome shape and

A display module comprising a display panel and a back plate sequentially coupled to a lower surface of a cover glass, wherein the cover glass has a pressure concentration portion corresponding to an area where pressure is concentrated on the display panel when the display panel and the back plate are bonded. , the back plate may have a first groove portion corresponding to the pressure concentration portion of the cover glass.

Details of other embodiments are included in the detailed description and drawings.

In the embodiments of the present specification, when the cover glass and the display module are bonded, a phenomenon in which the stress is non-uniformly combined or concentrated does not occur, so that the uniformity of the stress is constantly maintained along the bonding edge.

The present embodiments optimize the shape of the back plate that is a part of the display module and supports the rear surface of the display panel so that stable bonding with the cover glass is possible, thereby reducing the overall thickness of the display device, generating bubbles due to deformation and stress concentration, and It is possible to prevent the occurrence of wrinkles and improve the quality.

Since the contents of the invention described in the problems to be solved above, the means for solving the problems, and the effects do not specify the essential characteristics of the claims, the scope of the claims is not limited by the matters described in the contents of the invention.

1 is an exploded perspective view of a display device according to an embodiment of the present specification.
2A to 2B are side and rear views of a cover glass to which a display module is bonded.
3 is a plan view of measuring the pressure applied to the display panel in the prior art.
4 is a cross-sectional view of a display area and a non-display area of a display panel.
5 is a plan view illustrating a rear surface of the back plate according to an embodiment of the present specification.
6A to 6B are views illustrating a perspective view before the cover glass and the display module are coupled according to an embodiment, and a rear view after coupling.
7 is a cross-sectional view illustrating a cross section taken along line II′ of FIG. 6 .
8 is a plan view illustrating a rear surface of a back plate according to another embodiment of the present specification.
9A to 9B are views showing a perspective view before the cover glass and the display module are coupled and a rear view after coupling according to another embodiment;
10 is a cross-sectional view illustrating a cross section taken along line II-II' of FIG. 9B.
11 is a view showing a pressure change table according to the groove depth of the present specification.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative and the present invention is not limited to the illustrated matters. Like reference numerals refer to like elements throughout. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. When 'including', 'having', 'consisting', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, cases including the plural are included unless otherwise explicitly stated.

In interpreting the components, it is construed as including an error range even if there is no separate explicit description.

In the case of a description of the positional relationship, for example, when the positional relationship of two parts is described as 'on', 'on', 'on', 'beside', etc., 'right' Alternatively, one or more other parts may be positioned between two parts unless 'directly' is used.

In the case of a description of a temporal relationship, for example, 'immediately' or 'directly' when a temporal relationship is described with 'after', 'following', 'after', 'before', etc. It may include cases that are not continuous unless this is used.

Although the first, second, etc. are used to describe various elements, these elements are not limited by these terms. These terms are only used to distinguish one component from another. Accordingly, the first component mentioned below may be the second component within the spirit of the present invention.

In describing the components of the present specification, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the elements from other elements, and the essence, order, order, or number of the elements are not limited by the terms. When it is described that a component is “connected”, “coupled” or “connected” to another component, the component may be directly connected or connected to the other component, but other components may be interposed between each component. It should be understood that each component may be “interposed” or “connected”, “coupled” or “connected” through another component.

As used herein, the term "display device" refers to a liquid crystal module (LCM) including a display panel and a driving unit for driving the display panel, an organic light emitting module (OLED Module), and a quantum dot module (Quantum Dot Module). It may include a display device. And, LCM, OLED module, a finished product (complete product or final product) including QD module, such as notebook computers, televisions, computer monitors, automotive devices (automotive display) or other types of vehicles (vehicle) including the electric field A set electronic device such as an equipment display, a mobile electronic device such as a smart phone or an electronic pad, or a set device or set apparatus may also be included.

Accordingly, the display device in the present specification may include a set device that is a narrow display device itself, such as an LCM, an OLED module, a QD module, and an application product or an end-user device including an LCM, an OLED module, a QD module, etc. .

And, in some cases, the LCM, OLED module, and QD module composed of the display panel and the driving unit are expressed as a narrow “display device”, and the electronic device as a finished product including the LCM, OLED module, and QD module is “set” It can also be expressed as "device". For example, a display device in the narrow sense includes a liquid crystal (LCD), organic light emitting (OLED) or quantum dot display panel, and a source PCB that is a control unit for driving the display panel, and the set device is connected to the source PCB. It may be a concept further comprising a set PCB, which is a set controller that is electrically connected to control the entire set device.

The display panel used in this embodiment includes all types of liquid crystal display panels, organic light emitting diode (OLED) display panels, quantum dot (QD) display panels, electroluminescent display panels, etc. of the display panel may be used, and is not limited to a specific display panel capable of bezel bending with the flexible substrate for the organic light emitting (OLED) display panel and the lower back plate support structure of the present embodiment. In addition, the display panel used in the display device according to the embodiment of the present specification is not limited to the shape or size of the display panel.

For example, when the display panel is an organic light emitting (OLED) display panel, it may include a plurality of gate lines and data lines, and pixels formed at intersections of the gate lines and the data lines. In addition, an array including a thin film transistor as a device for selectively applying a voltage to each pixel, an organic light emitting device (OLED) layer on the array, and an encapsulation substrate or an encapsulation layer disposed on the array to cover the organic light emitting device layer (Encapsulation) and the like may be configured. The encapsulation layer may protect the thin film transistor and the organic light emitting device layer from external impact, and may prevent penetration of moisture or oxygen into the organic light emitting device layer. In addition, the layer formed on the array may include an inorganic light emitting layer, for example, a nano-sized material layer or quantum dots.

1 herein illustrates an exemplary organic electroluminescent (OLED) display panel 100 that may be incorporated into displays.

1 is an exploded perspective view illustrating a display device according to the present invention.

Referring to FIG. 1 , the display device 1 includes a dome-shaped cover glass 200 , a display panel 100 , a back plate 400 , a flexible printed circuit board (FPCB, 500), and A case 300 may be provided. An insertion groove 310 is formed in the case 300 so that the display panel 100 and the back plate 400 attached to the cover glass 200 can enter the inner insertion groove 310 of the case 300 . The display panel 100 , the back plate 400 , and the flexible printed circuit board 500 may constitute the display module 2 . The structure of FIG. 1 may be a structure applied to a smart watch, but is not limited thereto.

2A to 2B are views showing a comparative example of the display module 2 bonded to the cover glass 200 from the side and the rear side. Referring to FIG. 2A , there are a cover glass 200 , a display panel 100 attached to the cover glass 200 , and a flexible printed circuit board 500 , and the flexible printed circuit board 500 is the display panel 100 . It can be attached to the back. When the dome-shaped cover glass 200 is viewed from the side, a strain concentration part (SC) may be disposed on the edge side as shown in FIG. 2B . The pressure concentration portion SC of the cover glass 200 may be viewed as a midpoint between the central region where the image of the display device 1 is displayed and the outer bezel region. The cover glass 200 is obtained by removing a square shape having four corners from a spherical glass having a radius of curvature (R, Radius of Curvature) of about 100R. At this time, when the flat display panel 100 and the back plate 400 attached to the back are bonded to the spherical cover glass 200, in the region corresponding to the pressure concentration portion SC, the stress or pressure ( strain) is increased, and the panel may be lifted or air bubbles or wrinkles may occur.

Referring to FIG. 2B , the display panel 100 , the flexible printed circuit board 500 , and the back plate 400 are attached to the rear surface of the cover glass 200 . Since the area of the back plate 400 may be slightly larger than that of the display panel 100 , the display panel 100 may be sealed to the back plate 400 as shown in FIG. 2B , but is not limited thereto and may have the same area. Referring to FIG. 2B , a region corresponding to the pressure concentration portion SC of the cover glass 200 is expressed in an oval shape. Since the display panel 100 corresponds to the curved area in the pressure concentration portion SC, a stress or strain higher than that in the flat area may be applied.

FIG. 3 is a result of simulating the strain applied to the display panel 100 from the rear surface of FIG. 2B . Referring to FIG. 3 , it can be seen that a high strain is applied to a region corresponding to the pressure concentration portion SC of FIG. 2B . Due to the bonding of the flat display panel 100 and the back plate 400 to the spherical cover glass 200, an X-shaped strain non-uniformity portion appears as shown in FIG. 3, and in particular, the pressure concentration portion SC High pressure can be applied.

As such, defects such as bubbles and wrinkles may occur in the display panel 100 near the pressure concentration portion SC due to an imbalance of pressure applied to the display panel 100 . In addition, in small applications such as smart watches, there is not enough space to apply a heat dissipation sheet, so there may be a durability problem due to heat of the display panel 100 . If bubbles or wrinkles easily occur on the display panel 100 in a situation where the heat dissipation sheet is not applied, there may be a problem in reliability such as color abnormality of the screen corresponding to the pressure concentration part SC or deformation of the display panel 100. and may cause a yield problem to make up for it.

Referring to FIG. 3 , when the display panel 100 is attached to the cover glass 200 , the area where the maximum strain is concentrated may be about 13.67% of the total. This is the result of calculating the ratio of the pressure (strain) concentration area to the total area.

4 is a cross-sectional view illustrating a cross section of a display area A/A and a non-display area I/A of the display panel 100 . In the display panel 100 , thin film transistors 102 , 104 , 106 , 108 , organic light emitting devices 112 , 114 , 116 and various functional layers are positioned on a substrate 101 .

The substrate 101 may be a glass or plastic substrate. In the case of a plastic substrate, a polyimide-based or polycarbonate-based material may be used to have flexibility. In particular, polyimide is widely used as a plastic substrate because it can be applied to high-temperature processes and can be coated.

The buffer layer 130 is a functional layer for protecting the electrode/wire from impurities such as alkali ions leaking from the substrate 101 or the underlying layers. The buffer layer may be formed of silicon oxide (SiOx), silicon nitride (SiNx), or a multilayer thereof. The buffer layer 130 may include a multi buffer 131 and/or an active buffer 132 . The multi-buffer 131 may be formed by alternately stacking silicon nitride (SiNx) and silicon oxide (SiOx), and may delay diffusion of moisture and/or oxygen penetrating into the substrate 101 . The active buffer 132 protects the semiconductor layer 102 of the transistor and blocks various types of defects introduced from the substrate 101 . The active buffer 132 may be formed of, for example, amorphous silicon (a-Si).

The thin film transistor may have a form in which the semiconductor layer 102 , the gate insulating layer 103 , the gate electrode 104 , the interlayer insulating layer 105 , and the source and drain electrodes 106 and 108 are sequentially disposed. The semiconductor layer 102 is positioned on the buffer layer 130 . The semiconductor layer 102 may be made of polysilicon (p-Si), and in this case, a predetermined region may be doped with an impurity. In addition, the semiconductor layer 102 may be made of amorphous silicon (a-Si) or various organic semiconductor materials such as pentacene. Furthermore, the semiconductor layer 102 may be made of oxide. The gate insulating layer 103 may be formed of an insulating inorganic material such as silicon oxide (SiOx) or silicon nitride (SiNx), or may be formed of an insulating organic material or the like. The gate electrode 104 may be formed of various conductive materials, for example, magnesium (Mg), aluminum (Al), nickel (Ni), chromium (Cr), molybdenum (Mo), tungsten (W), gold (Au), or an alloy thereof. and the like.

The interlayer insulating layer 105 may be formed of an insulating material such as silicon oxide (SiOx) or silicon nitride (SiNx), and may also be formed of an insulating organic material. By selectively removing the interlayer insulating layer 105 and the gate insulating layer 103 , a contact hole through which the source and drain regions are exposed may be formed.

The source and drain electrodes 106 and 108 are formed on the interlayer insulating film 105 in the form of a single layer or a multi-layered electrode material. If necessary, a passivation layer made of an inorganic insulating material may cover the source and drain electrodes 106 and 108 .

A first planarization layer 107 - 1 may be disposed on the thin film transistor. The first planarization layer 107 - 1 protects the thin film transistor and the like and planarizes an upper portion thereof. The first planarization layer 107-1 may be configured in various forms, and may include an acrylic resin, an epoxy resin, a phenol resin, a polyamide-based resin, a polyimide-based resin, an unsaturated polyester-based resin, a polyphenylene-based resin, and a polyphenyl. It may be formed of at least one of lensulfide-based resins, but is not limited thereto.

Various metal layers serving as wires/electrodes may be disposed on the first planarization layer 107 - 1 .

The second planarization layer 107 - 2 is positioned on the first planarization layer 107 - 1 . The two planarization layers are due to an increase in various signal wirings as the display device 100 evolves to a high resolution. Therefore, it is difficult to arrange all the wirings on one layer while ensuring the minimum spacing, so an additional layer is created. This additional layer (second planarization layer) frees up wiring arrangement, making the wiring/electrode arrangement design easier. In addition, when a dielectric material is used as the planarization layers 107-1 and 107-2, the planarization layers 107-1 and 107-2 may be used to form capacitance between metal layers. have.

The organic light emitting device may have a form in which an anode electrode 112 , an organic light emitting layer 114 , and a cathode electrode 116 are sequentially disposed. That is, the organic light emitting device is composed of an anode electrode 112 formed on the planarization layer 107 , an organic light emitting layer 114 positioned on the anode electrode 112 , and a cathode electrode 116 positioned on the organic light emitting layer 114 . can

The anode electrode 112 may be electrically connected to the drain electrode 108D of the driving thin film transistor through the anode connection electrode 108 - 2 . When the organic light emitting diode display 100 is a top emission type, the anode electrode 112 may be made of an opaque conductive material having high reflectivity. For example, the anode electrode 112 may be formed of silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), chromium (Cr), or an alloy thereof. The anode connection electrode 108 - 2 may be made of the same material as the source and drain electrodes 106 and 108 .

The bank 110 is formed in the remaining area except for the light emitting area. Accordingly, the bank 110 has a bank hole exposing the anode electrode 112 corresponding to the emission region. The bank 110 may be made of an inorganic insulating material such as a silicon nitride film (SiNx) or a silicon oxide film (SiOx), or an organic insulating material such as BCB, an acrylic resin, or an imide resin.

The organic light emitting layer 114 is positioned on the anode electrode 112 exposed by the bank 110 . The organic light emitting layer 114 may include a light emitting layer, an electron injection layer, an electron transport layer, a hole transport layer, a hole injection layer, and the like.

The cathode electrode 116 is positioned on the organic light emitting layer 114 . When the display device 100 is a top emission type, the cathode electrode 116 is formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). As a result, the light generated in the organic light emitting layer 114 is emitted to the upper portion of the cathode electrode 116 .

The encapsulation layer 120 is positioned on the cathode electrode 116 . The encapsulation layer 120 prevents the penetration of oxygen and moisture from the outside in order to prevent oxidation of the light emitting material and the electrode material. When the organic light emitting diode is exposed to moisture or oxygen, a pixel shrinkage phenomenon in which the light emitting area is reduced may occur or a dark spot may occur in the light emitting area. The encapsulation layer may be formed of an inorganic film made of a glass, metal, aluminum oxide (AlOx) or silicon (Si)-based material, or may have a structure in which an organic film and an inorganic film are alternately stacked. The inorganic film serves to block the penetration of moisture or oxygen, and the organic film serves to planarize the surface of the inorganic film. The reason for forming the encapsulation layer as a multi-layered thin film layer is to make the movement path of moisture or oxygen longer and more complicated than that of a single layer, making it difficult to penetrate moisture/oxygen to the organic light emitting device.

Specifically, the encapsulation layer 120 may include a first inorganic insulating film 121 , an organic insulating film 122 , and a second inorganic insulating film 123 , and the first inorganic insulating film 121 , the organic insulating film 122 , The second inorganic insulating layers 123 may be sequentially disposed.

The barrier film 140 is positioned on the encapsulation layer 120 to encapsulate the entire substrate 101 including the organic light emitting diode. The barrier film 140 may be a retardation film or a photoisotropic film. When the barrier film has an optical isotropic property, light incident on the barrier film is transmitted as it is without a phase delay. In addition, an organic layer or an inorganic layer may be further disposed on the upper or lower surface of the barrier film. The organic or inorganic film formed on the upper or lower surface of the barrier film serves to block the penetration of external moisture or oxygen.

The adhesive layer 145 may be positioned between the barrier film 140 and the encapsulation layer 120 . The adhesive layer 145 adheres the encapsulation layer 120 and the barrier film 140 to each other. The adhesive layer 145 may be a heat-curable adhesive or a naturally-curable adhesive. For example, the adhesive layer 145 may be made of a material such as barrier pressure sensitive adhesive (B-PSA). A touch panel (film), a polarizing film, a top cover, and the like may be further positioned on the barrier film 140 .

The non-display area I/A may be located outside the display area A/A as illustrated, and a circuit unit (eg, GIP), a power line, and the like may be disposed thereon. The circuit unit may be disposed between the display area A/A at the end of the substrate 101 and may include a light emitting signal driver 161 and a scan signal driver 162 . A reference power voltage line 151 may be disposed between the circuit unit and an end of the substrate 101 , and a dam 190 may be disposed on the reference power voltage line 151 . The reference power voltage line 151 may be connected to the cathode electrode 116 of the display area A/A to provide a reference power to drive the organic light emitting diode. The dam 190 may prevent the organic insulating layer 122 of the encapsulation layer 120 from overflowing to the outside of the substrate 101 . The reference power voltage line 151 may be electrically connected to the connection electrode 152 disposed on the circuit unit. The planarization layer 107 covering the circuit part to be connected to the reference power voltage line 151 may be removed. The connection electrode 152 may extend and contact the reference power voltage line 151 exposed by removing the planarization layer 107 . The connection electrode 152 connected to the reference power voltage line 151 extends to the display area A/A and may be disposed on the circuit unit, and a part of the bank 110 covering the connection electrode 152 is removed. It may be electrically connected to the cathode electrode 116 through the space.

The first inorganic insulating film 121 , the organic insulating film 122 , and the second inorganic insulating film 123 are positioned on the cathode electrode 116 as the encapsulation layer 120 , so that the display area A/A as well as the non-display area are located. It is possible to cover the area adjacent to the dam 190 of (I/A), passing through the dam 190 and adjacent to the end of the substrate 101 . However, in the case of the organic insulating layer 122 , since the dam 190 is a structure for preventing the organic insulating layer 122 from overflowing, it may be disposed not to exceed the dam 190 as much as possible.

5 is an embodiment illustrating a rear plane of the back plate 400 . In order to solve the problem of imbalance of stress or strain of the display panel 100 corresponding to the pressure concentration part SC described in FIGS. 400), a method of forming a groove was derived. The back plate 400 may have a thickness of about 100 μm and a material may be made of polyethylene terephthalate (PET). Polyethylene terephthalate (PET) has good heat resistance, excellent turn properties and wrinkle resistance, and may be used as a function of supporting the back surface of the display panel 100 . While the performance of supporting the rear surface of the display panel 100 is good, the formability may be poor. Referring to FIG. 5 , a plurality of circular grooves and a plurality of linear grooves are disposed on the back plate 400 to solve the imbalance of stress or strain. The grooves disposed on the back plate 400 can be largely classified into three types. Referring to FIG. 5 , the first groove 401 is a circular groove and an area corresponding to the pressure concentration part SC of FIGS. 2B to 3 . And it may be disposed in the center of the back plate (400). In the second groove 402 , a groove having a smaller diameter than that of the first groove 410 may be disposed to connect the space between the first grooves 401 in an X-shape. Referring to FIG. 5 , about three second grooves 402 are arranged in the space between the plurality of first grooves 410 to form an X-shape on the back surface of the back plate 400 as a circular groove. . Five first grooves 401 may be disposed in the four corners and the central portion of the back plate 400 , and may have a size of about 2 mm in radius. Twelve second grooves 402 are arranged in groups of three each with a radius of about 1 mm in the space between the first grooves 410 .

Referring to FIG. 5 , a linear groove different from the first and second grooves 401 and 402 described above may be disposed on the outer edges of four surfaces of the back plate 400 . This may be called a third groove 403, and may have a width of about 0.7 mm and a length of about 17.9 mm to 24.2 mm.

By disposing the first grooves 401 to 403 on the back plate 400 to weaken elasticity or wrinkle resistance, the display panel 100 and the cover glass 200 may be well bonded. . Due to the bonding of the flat display panel 100 and the back plate 400 to the spherical cover glass 200, an X-shaped strain non-uniformity portion appears as shown in FIG. 3, and in particular, the pressure concentration portion SC High pressure can be applied.

As a method for forming a groove applied to the back plate 400 , a method of forming a groove in the back plate 400 before attaching to the display panel 100 and a method of forming a groove in the back plate 400 after attaching to the display panel 100 There may be a method of forming the groove. In both methods, a groove can be formed by irradiating a laser on the back plate and digging it. Among the two methods, in terms of reducing defects, it may be preferable to attach the display panel 100 as a single unit in which a groove is formed on the back plate 400 before attachment.

The back plate 400 may be attached to the rear surface of the display panel 100 using an adhesive layer PSA, and the adhesive layer may be formed to a thickness of about 25 μm.

6A to 6B are views illustrating a process in which the cover glass 200 and the display module 2 are bonded and a state after bonding according to the embodiment of FIG. 5 . When the display module 2 to which the display panel 100 and the back plate 400 are attached to the cover glass 200 is attached, the display module ( 2) It can be attached well without air bubbles or wrinkles.

FIG. 7 is a cross-sectional view taken along line II′ of FIG. 6B . Referring to FIG. 7 , the cover glass 200 , the display panel 100 , and the back plate 400 are sequentially attached, and among them, a first groove 401 and a second groove 402 are attached to the back plate 400 . It can be seen that they are placed The distance between the center points from the first groove 401 to the nearest second groove 402 may be about 4.0 mm, and the distance between the center points between the second grooves 402 may be about 3.5 mm.

FIG. 8 is a plan view illustrating another embodiment of the rear plane of the back plate 400 .

In order to solve the problem of imbalance of stress or strain of the display panel 100 corresponding to the pressure concentration part SC described in FIGS. 400), a method of forming a groove was derived. The back plate 400 may have a thickness of about 100 μm and a material may be made of polyethylene terephthalate (PET). Polyethylene terephthalate (PET) has good heat resistance, excellent turn properties and wrinkle resistance, and may be used as a function of supporting the back surface of the display panel 100 . While the performance of supporting the rear surface of the display panel 100 is good, the formability may be poor. Referring to FIG. 8 , a plurality of circular grooves are disposed on the back plate 400 to solve an imbalance between stress and strain. The grooves disposed in the back plate 400 may have the same shape and size, and the fourth grooves 404 may be disposed in a space between the pressure concentration parts SC and the pressure concentration parts SC of the cover glass 200 . Referring to FIG. 8 , the fourth groove 404 is a circular groove in the central portion of the back plate 400 and an area corresponding to the space between the pressure concentration portion SC and the pressure concentration portion SC of FIGS. 2B to 3 . A total of 9 can be arranged by placing them. The fourth groove may have a size of about 1.5 mm in radius.

By disposing the fourth grooves 404 on the back plate 400 to weaken elasticity or wrinkle resistance, the display panel 100 and the cover glass 200 may be well bonded.

9A to 9B illustrate a process in which the cover glass 200 and the display module 2 are bonded and a state after bonding according to the embodiment of FIG. 8 . When the display module 2 to which the display panel 100 and the back plate 400 are attached to the cover glass 200 is attached, the display module ( 2) It can be attached well without air bubbles or wrinkles.

FIG. 10 is a cross-sectional view taken along line II-II' of FIG. 9B. Referring to FIG. 10 , it can be seen that the cover glass 200 , the display panel 100 , and the back plate 400 are sequentially attached, and among them, fourth grooves 404 are disposed on the back plate 400 . . The distance between the center point of the fourth groove 404 and the adjacent fourth groove 404 may be about 15.3 mm.

11 shows the results of an experiment through the ABAQUS structural analysis program to compare the phenomenon of stress or strain according to the depth of the grooves arranged in the embodiments of FIGS. 5 to 8 did The condition is that the depth of the groove is divided into 5 conditions from 0 to 0.1 mm in the groove arrangement structure of the back plate 400 of FIG. 8, which is the first embodiment to the second embodiment, and is attached to the cover glass 200. 100) was simulated to measure the pressure (strain) applied to it.

Referring to FIG. 11 , the test was performed under five conditions of groove depths of 0 mm, 0.025 mm, 0.5 mm, 0.075 mm, and 0.1 mm. It can be seen that the point where the pressure is high is expressed in a dark red color on the image, and it can be seen that the point corresponding to the pressure concentration part SC of the cover glass 200 has a high pressure. From the simulation result, it can be seen that the maximum pressure (Strain) decreases and the high pressure zone (red region) decreases as the depth of the groove increases from condition 1 to condition 5, that is, as the depth of the groove increases.

It can be seen that in condition 5, when the depth of the groove is 0.1 mm, the pressure distribution applied to the display panel 100 is significantly lowered. Looking at the pressure distribution, it can be seen that even in the area corresponding to the pressure concentration portion SC of the cover glass 200 , the red high pressure area disappears and the area changes to a green or yellow area of relatively low pressure. Accordingly, the embodiments used in FIGS. 5 to 8 may try to minimize the pressure (Starin) applied to the display panel 100 by applying a depth of 0.1 mm.

Considering that the thickness of the back plate 400 is about 100 μm, the back plate 400 is almost removed from the region where the groove is formed, so that the display panel 100 may be exposed.

A display device according to an embodiment of the present specification includes a liquid crystal display device (LCD), a field emission display device (FED), an organic light emitting display device (OLED), It includes a Quantum Dot Display Device.

A display device according to an embodiment of the present specification is a laptop computer, a television, a computer monitor, an automotive display apparatus, or a vehicle, which is a complete product or final product including an LCM, an OLED module, and the like. A set electronic device apparatus or set device such as an electronic device including other types, such as an equipment display apparatus, a mobile electronic device apparatus such as a smart phone or an electronic pad, etc. ) may also be included.

A display device according to an embodiment of the present specification may be described as follows.

A display device according to an embodiment of the present specification includes a cover glass formed in a dome shape and

A display module comprising a display panel and a back plate sequentially coupled to a lower surface of a cover glass, wherein the cover glass has a pressure concentration portion corresponding to an area where pressure is concentrated on the display panel when the display panel and the back plate are bonded. , the back plate may have a first groove portion corresponding to the pressure concentration portion of the cover glass.

In the display device according to the exemplary embodiment of the present specification, the back plate may have a second groove portion corresponding to a region adjacent to the pressure concentration portion.

In the display device according to the exemplary embodiment of the present specification, the cover glass may have a constant radius of curvature.

In the display device according to the exemplary embodiment of the present specification, the first groove portion may have a circular shape.

In the display device according to the embodiment of the present specification, the second groove portion has a circular shape,

The first groove portion may have a larger radius than the second groove portion.

In the display device according to the exemplary embodiment of the present specification, the first groove portion and the second groove portion may have a circular shape having the same radius.

In the display device according to the exemplary embodiment of the present specification, the first groove portion may have a depth of about 100 μm.

In the display device according to the exemplary embodiment of the present specification, the first groove portion may expose the rear surface of the display panel.

The display device according to the embodiment of the present specification may include a case coupled to the lower surface of the cover glass and accommodating the display module.

A display device according to an embodiment of the present specification includes a display module including a cover glass, a display panel sequentially coupled to a lower surface of the cover glass, and a display module including a back plate, the cover glass including a pressure concentration portion and a first radius of curvature The back plate may have a first groove portion corresponding to the pressure concentration portion.

In the display device according to the exemplary embodiment of the present specification, the back plate may have a second groove portion corresponding to a peripheral area of the pressure concentration portion.

In the display device according to the exemplary embodiment of the present specification, the first groove portion may have a circular shape.

In the display device according to the embodiment of the present specification, the second groove portion has a circular shape,

The first groove portion may have a larger radius than the second groove portion.

In the display device according to the exemplary embodiment of the present specification, the first groove portion and the second groove portion may have a circular shape having the same radius.

In the display device according to the exemplary embodiment of the present specification, the first groove portion may have a depth of about 100 μm.

In the display device according to the exemplary embodiment of the present specification, the first groove portion may expose the rear surface of the display panel.

The display device according to the embodiment of the present specification may include a case coupled to a lower surface of the cover glass and accommodating the display module.

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

The present application described above is not limited to the above-described embodiment and the accompanying drawings, and it is common in the technical field to which this application belongs that various substitutions, modifications and changes are possible within the scope not departing from the technical matters of the present application. It will be clear to those who have the knowledge of Therefore, the scope of the present application is indicated by the following claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present application.

1: Display
101: substrate
102: semiconductor
103: gate insulating film
104: gate electrode
105: interlayer insulating film
106: source electrode
107-1: first planarization layer
107-2: second planarization layer
108: drain electrode
108-2: anode connection electrode
109: protective layer
110: bank
112: anode
114: organic light emitting layer
116: cathode
120: encapsulation layer
121: first inorganic insulating film
122: organic insulating film
123: second inorganic insulating film
130: buffer layer
131: multi buffer
132: active buffer
140: barrier film
145: adhesive layer
190 : dam
151 : VSS
152: connection electrode
161: light emitting signal driver
162: scan signal driver
200: cover glass
100: panel
300: case
310: insert groove
400: back plate
500 : FPC

Claims (17)

Cover glass formed in the shape of a dome; and
and a display module including a display panel and a back plate sequentially coupled to a lower surface of the cover glass,
The cover glass has a pressure concentration portion corresponding to a region where pressure is concentrated on the display panel when the display panel and the back plate are bonded,
The back plate has a first groove portion corresponding to the pressure concentration portion of the cover glass.
The method of claim 1,
The back plate has a second groove portion corresponding to a region adjacent to the pressure concentration portion.
The method of claim 1,
The cover glass has a constant radius of curvature.
3. The method of claim 2,
The first groove portion has a circular shape.
5. The method of claim 4,
The second groove portion has a circular shape,
The first groove portion has a larger radius than the second groove portion.
5. The method of claim 4,
The display device has a circular shape having the same radius as the first groove portion and the second groove portion.
The method of claim 1,
The first groove portion has a depth of about 100 μm.
8. The method of claim 7,
The first groove portion exposes a rear surface of the display panel.
The method of claim 1,
and a case coupled to a lower surface of the cover glass and accommodating the display module.
cover glass; and
and a display module including a display panel sequentially coupled to a lower surface of the cover glass and a back plate,
The cover glass is formed to include a pressure concentration portion and to have a first radius of curvature,
The back plate has a first groove portion corresponding to the pressure concentration portion.
11. The method of claim 10,
The back plate has a second groove portion corresponding to a peripheral area of the pressure concentration portion.
12. The method of claim 11,
The first groove portion has a circular shape.
13. The method of claim 12,
The second groove portion has a circular shape,
The first groove portion has a larger radius than the second groove portion.
13. The method of claim 12,
The display device has a circular shape having the same radius as the first groove portion and the second groove portion.
11. The method of claim 10,
The first groove portion has a depth of about 100 μm.
16. The method of claim 15,
The first groove portion exposes a rear surface of the display panel.
11. The method of claim 10,
and a case coupled to a lower surface of the cover glass and accommodating the display module.

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