Curved screen and display device

A curved screen and a display device are disclosed. The curved screen includes a first substrate, a second substrate, and a liquid crystal layer disposed between the first and second substrates. The curved screen is bent and concave along the first substrate. The first substrate includes a substrate and a planarization layer disposed on a concave side of the substrate. A plurality of grooves are defined in the planarization layer and arranged at intervals along a direction of a bending edge of the curved screen, and extend in parallel along a direction of a non-bending edge. The depth of each groove before bending is greater than after bending.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority and benefit of Chinese patent application 2021114443240, entitled “Curved Screen and Display Device” and filed Nov. 30, 2021, with China National Intellectual Property Administration, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present application relates to the field of display technology, and in particular, to a curved screen and a display device.

BACKGROUND

The description provided in this section is intended for the mere purpose of providing background information related to the present application but doesn't necessarily constitute prior art.

With the development of display technology, Thin Film Transistor-Liquid Crystal Display (TFT-LCD) has become the mainstream display used in daily life and work. It has advantages of low cost, mature production techniques, and consummate upstream and downstream supporting facilities. TFT-LCD has experienced the development in different eras, and a curved screen is derived from a flat screen. A curved TV allows every point on the screen to reach the eye at an equal distance, allowing viewers to enjoy a good viewing experience with the edges. The curved screen TV can bring the audience a wider field of view and a thrill feeling, showing that the curved screen design not only changes the appearance of traditional TVs, but also further improves the viewing effect. However, so far, the production process of the curved screen consists in fixing a flat LCD display screen to a template of the display by bending it with an external force in order to assemble it into a TV.

Specifically, when the display panel changes from a flat shape to a shape curved, for example, the inner side of the color filter substrate is stretched under stress and meanwhile the inner side of the array substrate is compressed due to stress. Because the planarization layer is relatively thicker so that it forms irregular bumps after being squeezed by stress, causing the alignment of the liquid crystal at this position to be different from other normal positions, thereby resulting in light leakage, and vice versa, affecting the display effect after the curved screen is bent. Therefore, those skilled in the art need to provide a solution to alleviate or solve this problem.

SUMMARY

In view of the above, it is a purpose of the present application to provide a curved screen, so that the display effect of the curved screen will not be significantly affected while the viewing angle is superior.

The present application discloses a curved screen, including a first substrate, a liquid crystal layer and a second substrate. The curved screen is bent and concave along the first substrate. A liquid crystal layer is disposed between the first substrate and the second substrate. The first substrate includes a substrate and a planarization layer. The planarization layer is disposed on the concave side of the substrate. A plurality of grooves are defined in the planarization layer along a bending edge direction of the curved screen. The groove extends in a direction perpendicular to the bending direction. The depth of the groove before bending is greater than the depth of the groove after bending.

Optionally, the groove is a V-shaped structure.

Optionally, the first substrate includes a substrate, an insulating layer, a passivation layer, a color filter layer and a planarization layer. The insulating layer is disposed on the substrate. The passivation layer is disposed on the insulating layer. The color filter layer is disposed on the passivation layer. The planarization layer is disposed on the color filter layer. The thickness of the substrate is L1. The sum of the thicknesses of the insulating layer and the passivation layer is L2. The thickness of the color filter layer is L3. The thickness of the planarization layer is L4. The length of the curved screen along the bending edge is X, and the bending curvature is K. The number of the grooves is H, and the length of the grooves is consistent with the length of the curved screen perpendicular to the bending direction. The width of the groove along the bending edge is a, and the depth of the groove is b, then ab≥2XK(L3+L4)(L1+L2+L3+L4)/H.

Optionally, the grooves are strip-shaped grooves and are evenly arranged. After the curved screen is bent, the surface of the groove is a curved surface. The bending direction of the curved surface is consistent with the bending direction of the curved screen.

Optionally, the first substrate is an array substrate. The second substrate is a color filter substrate. The array substrate includes a substrate, an insulating layer, a plurality of data lines, a passivation layer and a planarization layer. The insulating layer is formed on the substrate. The plurality of data lines are arranged on the insulating layer. The passivation layer is formed on the data lines. The planarization layer is formed on the passivation layer. The light shielding portion corresponds to the data lines. The groove is provided in the planarization layer corresponding to each of the data lines. The curved screen further includes a light-shielding portion, and the light-shielding portion is located on the array substrate or the color filter substrate and is disposed corresponding to the data line.

Optionally, the first substrate is an array substrate. The second substrate is a color filter substrate. The array substrate includes a substrate, a plurality of columns of thin film transistors and a planarization layer. The plurality of columns of the thin film transistors are arranged on the substrate and arranged along a direction perpendicular to the bending direction. The planarization layer is disposed on the thin film transistor. The grooves are provided in the planarization layer corresponding to the positions of the thin film transistors in each column.

Optionally, the array substrate further includes a color filter layer, and the color filter layer is disposed between the passivation layer and the planarization layer. The color filter layer includes at least a first color filter and a second color filter. A connecting portion is disposed adjacent to the first color filterer and the second color filterer. The connecting portion is disposed corresponding to the data line and the light shielding portion. The planarization layer is provided with the groove corresponding to the connecting portion.

Optionally, the first substrate is a color filter substrate. The second substrate is an array substrate. The color filter substrate includes a substrate, a color filter layer and a planarization layer. The color filter layer is formed on the substrate. The planarization layer is formed on the color filter layer. The color filter layer includes at least a first color filter and a second color filter. A connecting portion is disposed adjacent to the first color filterer and the second color filterer. The planarization layer is provided with the groove corresponding to the connecting portion.

Optionally, the depth of the groove is 0.1 um-1 um, and the width of the groove along the bending direction is 2 um-20 um.

The present application further discloses a display device comprising a curved screen and a backlight module, wherein the curved screen is installed on one side of the backlight module, and the backlight module provides a backlight source for the curved screen.

Compared with the related art in which a bulge is generated during bending and the position of the bulge is uncontrollable, in the present application, a plurality of grooves are provided in the planarization layer along the bending direction of the curved screen. Because the surface of the curved screen is subjected to stress extrusion when the curved screen is bent, it can improve the situation in which the planarization layer is relatively thick and the film layer is likely to form irregular bulges after extrusion. First of all, the existence of the grooves makes the position where the stress concentrates controllable during bending. When bending, the compression of the substrate is concentrated at the position of the groove, and we can control the position of the “bump” that is prone to display problems, so as to reduce the influence of the display problem on the actual display effect (for example, the groove can be disposed in the non-display area or the position of the light-shielding structure). Furthermore, with such a design, the depth of the groove after the bending is smaller than that before the bending, so as to offset the compressive force of the bending and reduce the occurrence of bulges. The problem of uneven cell thickness after bending can be improved, so that while the viewing angle of the curved screen100is excellent, the display effect will not be significantly affected.

DETAILED DESCRIPTION OF EMBODIMENTS

It should be understood that the terminology used herein, the specific structural and functional details disclosed are intended for the mere purpose of describing specific embodiments and are relatively representative, which should however not be construed as limited only the embodiments set forth herein.

In the description of this application, the terms “first” and “second” are merely used for description purposes, and cannot be understood as indicating relative importance, or implicitly indicating the number of indicated technical features. Thus, unless otherwise specified, features defined as “first” and “second” may expressly or implicitly include one or more of the features; “plurality” means two or more. The terms “including”, “comprising”, and any variations thereof are intended to mean a non-exclusive inclusion, namely one or more other features, integers, steps, operations, units, components and/or combinations thereof may be present or added.

In addition, terms such as “center”, “transverse”, “lateral”, “above”, “on”, “under”, “below”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “out-side”, etc., indicative of orientations or positional relationships are described based on the orientations or relative positional relationships illustrated in the drawings, and are intended for the mere purpose of convenience of simplified description of the present application, rather than indicating that the device or element referred to must have a specific orientation or be constructed, and operate in a particular orientation. Thus, these terms should not be construed as limiting the present application.

In addition, unless otherwise expressly specified and defined, terms “installed on”, “connected to”, and “coupled to” should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection, or may also be an electrical connection; it may be a direct connection, an indirect connection through an intermediate medium, or an internal connection between two components. For those having ordinary skill in the art, the specific meanings of the above terms in this application can be understood depending on specific contexts

The present application will be described in detail below with reference to the accompanying drawings and optional embodiments.

First Embodiment

FIG.1is a schematic diagram of a curved screen provided by a first embodiment of the present application.FIG.2is a schematic top view of a curved screen provided by the first embodiment of the present application.FIG.3is a schematic diagram of a cross-sectional structure of a curved screen provided by the first embodiment of the present application. As shown inFIG.2, the present application discloses a curved screen. The curved screen has four sides, where the upper and lower sides are bending edges, and the left and right sides are non-bending edges. A plurality of grooves are arranged in parallel along the direction of the non-bending edge. The length of each of the plurality of grooves is the length extending along the non-bending edge of the curved screen, and the width of the groove is the width along the direction of the bending edge. In particular, referring toFIGS.1-3, a curved screen100includes a first substrate110, a liquid crystal layer140and a second substrate130. The curved screen is bent and concave along the first substrate. A liquid crystal layer140is disposed between the first substrate110and the second substrate130. The first substrate110includes a substrate111and a planarization layer112. The planarization layer112is disposed on the concave side of the substrate111. A plurality of grooves113are provided in the planarization layer112along the direction of the bending edge of the curved screen100, and the grooves113extend in a direction perpendicular to the direction of the bending edge. The depth of the groove113before bending is greater than the depth of the groove113after bending.

In the present application, a plurality of grooves113are provided in the planarization layer112along the bending direction of the curved screen100. Because the surface of the curved screen100is subjected to stress extrusion when the curved screen100is bent, it can improve the situation in which the planarization layer112is relatively thick and the film layer is likely to form irregular bulges after extrusion. First of all, the existence of the grooves113makes the position where the stress concentrates controllable during bending. When bending, the compression of the substrate is concentrated at the position of the groove113, and we can control the position of the “bump” that is prone to display problems, so as to reduce the influence of the display problem on the actual display effect (for example, the groove113can be disposed in the non-display area or the position of the light-shielding structure). Furthermore, with such a design, the depth of the groove113after the bending is smaller than that before the bending, so as to offset the compressive force of the bending and reduce the occurrence of bulges. The problem of uneven cell thickness after bending can be improved, so that while the viewing angle of the curved screen100is excellent, the display effect will not be significantly affected.

Specifically, the groove113is a V-shaped structure. The groove113of the V-shaped structure has a large accommodating width and has only one corner. In this way, during the bending process, the two groove walls of the groove113are adjacent to each other along the bending direction and then closed. The V-shaped shape closes more tightly and is more uniform, and it is not easy to cause bulge after bending. Even if there is a bulge after bending, the positioning of the bulge is more controllable and is a unique position, so that the follow-up repair is relatively more targeted. Of course, the groove113may not adopt a V-shaped structure, but may adopt an arc-shaped structure, a concave-shaped structure or a U-shaped structure, etc., as long as there is enough space for accommodating stress and the deformation of the groove113can be relatively uniform when the curved screen100is bent, so that the film structure is relatively flat after the curved screen100is bent, and no bulge occurs.

Further,FIG.4is a schematic diagram of the first substrate provided by the first embodiment of the present application. As shown inFIG.4, the first substrate110includes a substrate111, an insulating layer116, a passivation layer117, a color filter layer118and a planarization layer112. The insulating layer116is disposed on the substrate111. The passivation layer117is disposed on the insulating layer116. The color filter layer118is disposed on the passivation layer117. The planarization layer117is disposed on the color filter layer118. The thickness of the substrate111is L1. The sum of the thicknesses of the insulating layer116and the passivation layer117is L2. The thickness of the color filter layer118is L3. The thickness of the planarization layer112is L4. The length of the curved screen100along the bending edge is X. The curvature of the bend is K. The number of the grooves113is H. The length of the groove113is consistent with the length of the curved screen100perpendicular to the bending direction. The width of the groove113along the bending edge is a and the depth is b, so ab≥2XK(L3+L4)(L1+L2+L3+L4)/H.

Specifically, in the case of a flat screen, the volume of the first substrate110of the display panel is V1and the length is X, and V1=X*Y(L3+L4).

After the display panel is bent, there is no bulge and the inner side of the first substrate110is flat, the volume of the first substrate110is V2. The length of the outer surface of the first substrate110of the display panel after bending is X, and the length of the inner surface is X1, V2=X1*Y*(L3+L4), X1=X/2π*1/K(1/K−L1−L2−L3−L4).

Therefore, the volume difference before and after bending: ΔV=X*Y(L3+L4)K(L1+L2+L3+L4), and the volume difference of this part is the total volume of all grooves113.

Therefore, according to the total volume of the grooves113, the cross-sectional area of the grooves113can finally be calculated as ab≥XK(L3+L4)(L1+L2+L3+L4)/H. Furthermore, for example, the number of grooves113may be equal to the number of data lines120, etc., which can be selected depending on specific conditions. Theoretically, the groove113calculated in this way can make the sidewalls of the groove113completely closed under the bending state, which can ensure that the size of the groove113can be changed within a controllable range. When the screen is changed from straight to curved, the film layer will not be raised, and at this time ab=XK(L3+L4)(L1+L2+L3+L4)/H.

The depth of the groove113is 0.1 um-1 um, and the width of the groove113along the bending direction is 2 um-20 um. In this way, it is possible to choose the size of the groove113to be dug according to the size range of the groove, and the size of the groove113can be set accurately according to the size of the curvature of the curved screen100, and the precision is relatively higher. In some embodiments, the depth of the groove113is 0.4 um, and the width of the groove113along the bending direction is 8 um.

Optionally, the grooves113are strip-shaped grooves and are evenly arranged. After the curved screen100is bent, the surface of the groove113is a curved surface, and the bending direction of the curved surface is consistent with the bending direction of the curved screen100. That is, referring to the above formula, the groove113can be designed to be slightly larger namely ab>2XK(L3+L4)(L1+L2+L3+L4)/H, so that when the curved screen100is bent, the film layers are squeezed against each other and the groove113has enough space to release the stress, while ensuring that the deformation of the groove113after bending is just within the prepared bending space, so that the possibility of the film layer bulging due to the change of topography after bending can be reduced. In addition, the grooves are strip-shaped grooves and are evenly arranged, so that the extrusion stress of the curved screen is relatively concentrated when it is bent, and the effect of stress relief is better. In this way, when the curved screen is bent, each strip-shaped groove is synchronously closed, which can release the extrusion stress more uniformly, and avoid causing a bulge at a single position to affect the display effect.

Second Embodiment

FIG.5is a schematic diagram of a cross-sectional structure of a curved screen provided by a second embodiment of the present application. As shown inFIG.5, the difference between this embodiment and the first embodiment is that the first substrate110is an array substrate, and the second substrate130is a color filter substrate. The array substrate includes a substrate111, an insulating layer116, a plurality of data lines120, a passivation layer117and a planarization layer112. The insulating layer116is formed on the substrate111. The plurality of data lines120are disposed on the insulating layer116. The passivation layer117is formed on the data line120. The planarization layer112is formed on the passivation layer117. The groove113is provided in the planarization layer112corresponding to each of the data lines120. The curved screen100further includes a light shielding portion131, the light shielding portion131is located on the array substrate or the color filter substrate, and is disposed corresponding to the data line120. The data line120is arranged perpendicular to the bending direction of the curved screen100. In addition, the position of the data line120is also relatively prone to bulge. Correspondingly, the groove113is provided at the position of each data line120, which can reduce the bulge problem at the position of the data line120. In addition, the position of the data line120is provided with a light shielding portion131, and the light shielding portion131can also be used to improve the problem of uneven display of the groove113. Furthermore, the arrangement of the data lines120is also uniform, so the spacing of the grooves113on the curved screen100is also uniform. When the curved screen100is bent, stress is generated by extrusion between the film layers, and the uniformly arranged grooves113also release the generated stress uniformly at this time. Through each groove113, the stress generated by extrusion can be uniformly dispersed, which can prevent the phenomenon that a certain position of the film layer bulges due to uneven release of stress, and further ensures the flatness of the film layer topography after bending. Of course, the number of the data lines120and the number of the grooves113may be set in one-to-one correspondence or in proportion, for example, two data lines120are correspondingly provided with one groove113.

Third Embodiment

FIG.6is a schematic diagram of a cross-sectional structure of a curved screen according to a third embodiment of the present application. As shown inFIG.6, the difference between this embodiment and the first and second embodiments is that the first substrate110is an array substrate, and the second substrate130is a color filter substrate. The array substrate includes a substrate111, a plurality of columns of thin film transistors119and a planarization layer112. The plurality of columns of the thin film transistors119are arranged on the substrate111and arranged along a direction perpendicular to the bending direction of the curved screen100. The planarization layer112is disposed on the thin film transistor119. The groovees113are provided in the planarization layer112corresponding to the positions of the thin film transistors119in each column. In this way, the array substrate is the outer substrate of the curved screen100. The thin film transistors119in the array substrate are formed by stacking multiple layers, which so are prone to bulge due to extrusion during the bending process when the curved screen100is bent. Therefore, arranging the groovees113in the planarization layer112corresponding to the positions above the thin film transistors119of each column can prevent the positions where the thin film transistors119are stacked from being raised due to stress extrusion during bending. Thus, the performance of the thin film transistors119is not affected, thereby ensuring that the display effect of the curved screen100before and after the bending is basically the same.

The groovees113are arranged at the positions corresponding to the thin film transistors119and may be arranged in combination with the positions of the data lines120. At this time, the grooves113can be set as short grooves. Of course, the grooves113may also be provided independently corresponding to the channels of the thin film transistors119, and in this case, the grooves113run through the entire curved screen.

Fourth Embodiment

FIG.7is a schematic diagram of a cross-sectional structure of a curved screen provided by a fourth embodiment of the present application. As shown inFIG.7, the difference between this embodiment and the first, second, and third embodiments is that the array substrate further includes a color filter layer118. The color filter layer118is disposed between the passivation layer117and the planarization layer112. The color filter layer118includes at least a first color filter121and a second color filter122. A connecting portion123is disposed adjacent to the first color filter121and the second color filter122. The connecting portion123is disposed corresponding to the data line120and the light shielding portion131. The grooves113are formed in the planarization layer112corresponding to the connecting portions123.

At the connecting portion123disposed adjacent to the first color filter121and the second color filter122, they only abut but does not overlap. The groove113is provided at the abutting portion of the connecting part123, which can prevent the curved screen100from being raised at the abutting portion after bending. Furthermore, at this time, the light shielding portion131is disposed corresponding to the position of the connecting portion123, which can also prevent the risk of light leakage from the connecting portion123of the first color filter121and the second color filter122, thereby double ensuring the display effect of the curved screen100.

Of course, the first color filter121and the second color filter122can also overlap each other.FIG.8is a schematic cross-sectional diagram of a curved screen in which the first color filter and the second color filter of the present application overlap each other. As shown inFIG.8, at the connecting portion123disposed adjacent to the first color filter121and the second color filter122, they overlap each other. At this time, the film layer at the overlapping portion of the connecting portion123is significantly thicker, and the probability of bulging at the overlapping portion of the two color filters after the curved screen100is bent is high. Therefore, the groove113is arranged above the corresponding position of the connecting portion123, and the extrusion stress can be concentrated and changed in the groove113for the release of the extrusion stress of the film layer where the color filter overlaps due to bending, thereby preventing bulging at the overlap of two color filters due to bending.

FIG.9is a schematic diagram of the groove in the area A ofFIG.8before and after bending. As shown inFIG.9, the dotted line in the figure denotes the groove113before the curved screen is bent. The depth of the groove113after the curved screen100is bent will change due to the extrusion stress of the stacked film layers. Therefore, according to the design of the width and depth of the groove113, the extrusion stress of the groove113after the curved screen100is bent can be changed within the range of the groove113, so as to avoid the possibility of bulging as much as possible and ensure that the display effect is the same before and after bending.

Fifth Embodiment

FIG.10is a schematic diagram of a cross-sectional structure of a curved screen provided by a fifth embodiment of the present application. As shown inFIG.10, the present embodiment is different from the first, second, third and fourth embodiments in that the groove113includes a first groove114and a second groove115. The first groove114is disposed in the planarization layer112. The second groove115is disposed in the insulating layer116. The first groove114and the second groove115correspond to the connecting portion123. In this way, the film layer of the insulating layer116corresponding to the connecting portion123sinks, and the second groove115can release a part of the stress generated by the extrusion when the curved screen100is bent, and the change of the film layer the corresponding to the position where the color filters overlap due to extrusion is relatively smaller. The corresponding first groove114in the planarization layer112and the second groove115cooperate with each other to release the extrusion stress in the two film layers respectively, which can further ensure that the curved screen100is less likely to bulge at the overlap of the two color filters after bending, and ensures the flatness of the topography of the film layer after bending.

Sixth Embodiment

FIG.11is a schematic diagram of a curved screen provided by a sixth embodiment of the present application.FIG.12is a schematic diagram of a cross-sectional structure of a curved screen provided by the sixth embodiment of the present application. Referring toFIGS.11-12, the difference between this embodiment and the first, second, third, fourth and fifth embodiments is that the bending direction of the curved screen100is compressed and bent along the inner side of the color filter substrate. The first substrate110is a color filter substrate. The second substrate130is an array substrate. The color filter substrate includes a substrate111, a color filter layer118and a planarization layer112. The color filter layer118is formed on the substrate111. The planarization layer112is formed on the color filter layer118. The color filter layer118includes at least a first color filter121and a second color filter122. A connecting portion123is disposed adjacent to the first color filter121and the second color filter122. The groove113is formed in the planarization layer112corresponding to the connecting portion123. Because in the COA (Color-filter on Array) panel, the problem of bulging at the overlap between the two color filters in the color filter layer118is relatively serious. Therefore, grooves113are provided in the planarization layer112in the color filter substrate at a position corresponding to the connecting portion123between two adjacent color filters. When the curved screen100is bent, the groove113correspondingly changes the extrusion stress within the groove113, which can prevent the connecting portion123from bulging due to extrusion, and prevent the risk of light leakage from the connecting portion123, thereby ensuring the display effect of the curved screen100.

FIG.13is a schematic diagram of a display device of the present application. As shown inFIG.13, the present application further discloses a display device10including a curved screen100and a backlight module200. The curved screen100is installed on one side of the backlight module200. The backlight module200provides a backlight source for the curved screen100. The display device10provided with the curved screen100can make each point on the screen reach the same distance to the eyes, and the audience can also enjoy a good viewing experience from the edges. The display device10with the curved screen100can bring the audience a wider field of vision and thrill feeling.

The technical solutions of the present application may be widely used in various display panels, such as TN (Twisted Nematic) display panels, IPS (In-Plane Switching) display panels, VA (Vertical Alignment) display panels, and MVA (Multi-Domain Vertical Alignment) display panels. Of course, the above solutions are also applicable to other types of display panels, such as OLED (Organic Light-Emitting Diode) display panels.

It should be noted that the inventive concept of the present application can also form other embodiments, and is not limited to the above description, but the length of the application documents is limited so that the embodiments cannot be enumerated one by one. For those having ordinary skill in the technical field of the present application, without departing from the scope and spirit of the present application, some simple deductions or substitutions can be made, which should all be regarded as falling in the scope of protection of the present application.