TWI662325B - Display device - Google Patents

Abstract

The invention discloses a display device including a display panel and a composite back plate on the back side thereof. The composite back plate has a first plate body and a second plate body. The first plate has a first connection surface, and has a first bending pre-force to be resiliently bent. The second plate has a second connecting surface facing the first connecting surface and is at least partially connected with the first connecting surface. The second plate body has a second bending pre-force and is resiliently bent corresponding to the first plate body. Among them, the internal force of the connection between the first connection surface and the second connection surface is balanced with the first bending pre-force and the second bending pre-force to maintain the curvature of the first plate body and the second plate body.

Description

Display device

The invention relates to a display device, in particular to a curved display device with a curved back plate.

With the development of display technology, in addition to improvements in size and picture quality, the appearance of display devices has also changed, such as curved display devices. Compared with flat display devices, curved display devices can not only be made larger in the same width, curved display devices can also provide better viewing effects.

Traditionally, the curvature control of the display panel of a curved display device is pre-curved by a bracket behind the single-layer backplane or itself through a mold. However, no matter which method is used, the accuracy of the curvature is difficult to control.

The purpose of the present invention is to provide a display device with better curvature control for the back plate, and only requires simple jig assistance in assembly. In addition to providing a thinner, narrower frame and beautiful design, it can also reduce production costs.

In view of this, the present invention provides a display device including a display panel and a composite back plate on the back side thereof. The composite back plate has a first plate body and a second plate body. The first plate has a first connection surface, and has a first bending pre-force to be resiliently bent. The second plate has a second connecting surface facing the first connecting surface and is at least partially connected with the first connecting surface. The second plate has a second bending pre- The first plate is flexibly resiliently bent.

Among them, the internal force of the connection between the first connection surface and the second connection surface is balanced with the first bending pre-force and the second bending pre-force to maintain the curvature of the first plate body and the second plate body.

In another embodiment, the present invention provides a display device including a display panel having a curvature and a synthetic back plate located on a back side of the display panel. The composite back plate is curved corresponding to the display panel. The composite back plate has a first plate body and a second plate body. The first plate body has a first connection surface, and the second plate body has a second connection surface facing the first connection surface and is at least partially connected to the first connection surface. The second plate is curved corresponding to the first plate.

The thickness ratio of the first plate body to the second plate body is between 0.43 and 2.33.

In another embodiment, the present invention provides a display device including a curved display panel, a support frame, and a composite back plate. The support frame supports at least a part of the periphery of the display panel. The composite back plate is disposed on a side of the support frame facing away from the display panel, and is bent corresponding to the display panel. The composite back plate has a first plate body and a second plate body. The first plate body has a first connection surface, and the second plate body has a second connection surface facing the first connection surface and is at least partially connected to the first connection surface. The second plate is curved corresponding to the first plate.

Wherein, one of the first plate body or the second plate body has an end portion protruding beyond the other, and the support frame is fixedly connected to the end portion.

1‧‧‧ display device

11‧‧‧Display Panel

111‧‧‧display surface

112‧‧‧ dorsal

12‧‧‧ synthetic backplane

121‧‧‧ the first plate

122‧‧‧Second plate

123‧‧‧adhesive layer

124‧‧‧ support frame

125‧‧‧ Cavity

1211‧‧‧first connection surface

1212‧‧‧first end

1221‧‧‧Second connection surface

1222‧‧‧ second end

1241‧‧‧ bottom

1242‧‧‧Top

2‧‧‧ display device

21‧‧‧Display Panel

211‧‧‧display surface

212‧‧‧ dorsal

22‧‧‧ synthetic backplane

221‧‧‧First plate

222‧‧‧Second plate

223‧‧‧Adhesive layer

224‧‧‧Support frame

225‧‧‧ Cavity

2211‧‧‧First connecting surface

2212‧‧‧first end

2221‧‧‧Second connection surface

2222‧‧‧ second end

2241‧‧‧ bottom

2242‧‧‧Top

F1‧‧‧Tension, Shear Stress

F2‧‧‧Tension and Shear Stress

F3‧‧‧Tension and Shear Stress

F4‧‧‧Tension, Shear Stress

Θ1‧‧‧ angle

Θ2‧‧‧ angle

Θ3‧‧‧ angle

Θ4‧‧‧ angle

FIG. 1 is an exploded view of a force body of an embodiment of a display device of the present invention.

FIG. 2 is a side view of the embodiment of FIG. 1. FIG.

FIG. 3 is a schematic diagram of a curved embodiment of a display device according to the present invention.

FIG. 4 is an assembly diagram of the embodiment of FIG. 3.

FIG. 5 is a schematic diagram of the stress of the synthetic backplane of the present invention.

FIG. 6 is a schematic diagram of another embodiment of a display device according to the present invention.

FIG. 7 is a schematic diagram of another embodiment of a display device according to the present invention.

FIG. 8 is a schematic diagram of another embodiment of a display device according to the present invention.

FIG. 9 is a schematic diagram of another curved embodiment of the display device of the present invention.

FIG. 10 is an assembly diagram of the embodiment of FIG. 9.

In the following, a plurality of embodiments of the present invention will be disclosed by means of drawings and text descriptions. For the sake of clear description, many practical details will be described in the following description. It should be understood, however, that these practical details should not be used to limit the invention. In addition, in order to simplify the drawings, some commonly used structures and components will be drawn in a simple and schematic way in the drawings.

In the drawings, the thicknesses of layers, films, panels, regions, etc. are exaggerated for clarity. Throughout the description, the same reference numerals denote the same elements. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element, or Intermediate elements may also be present. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, there are no intervening elements present. "Connected" as used herein may refer to a physical and / or electrical connection.

It should be understood that, although the terms "first," "second," "third," etc. may be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, and / or sections, and / Or in part should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a "first element," "component," "region," "layer," or "portion" discussed below may be referred to as a second element, component, region, layer, or section without departing from the teachings herein.

In addition, relative terms such as "lower" or "bottom" and "upper" or "top" may be used herein to describe the relationship of one element to another element, as shown. It should be understood that relative terms are intended to include different orientations of the device in addition to the orientation shown in the figures. For example, if the device in one of the figures is turned over, elements described as being on the "lower" side of other elements would then be oriented on "upper" sides of the other elements. Thus, the exemplary term "under" may include orientations of "under" and "upper" depending on the particular orientation of the drawings. Similarly, if the device in one of the figures is turned over, elements described as "below" or "beneath" other elements would then be oriented "above" the other elements. Thus, the exemplary terms "below" or "below" may include orientations above and below.

As used herein, "about", "approximately" or "substantially" includes the stated value and the average value within an acceptable deviation range of a particular value determined by one of ordinary skill in the art, taking into account the measurements in question and the measurements A specific number of related errors (for example: limitations of the measurement system). For example, "about" can mean within one or more standard deviations of the stated value, or within ± 30%, ± 20%, ± 10%, ± 5%. Furthermore, "about", "approximately" or "substantially" as used herein may select a more acceptable range of deviations or standard deviations based on optical properties, etching properties, or other properties, and all properties can be applied without one standard deviation .

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted to have meanings consistent with their meanings in the context of the related art and the present invention, and will not be interpreted as idealized or excessive Formal meaning unless explicitly defined as such in this article.

Exemplary embodiments are described herein with reference to cross-sectional views that are schematic views of idealized embodiments. Accordingly, variations in the shapes of the illustrations as a result, for example, of manufacturing techniques and / or tolerances, are to be expected. Therefore, the embodiments described herein should not be construed as limited to the particular shape of the area as shown herein, but include shape deviations caused by, for example, manufacturing. For example, a region shown or described as flat may generally have rough and / or non-linear characteristics. Furthermore, the acute angles shown may be round. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the claims.

Please refer to FIG. 1 and FIG. 2, which are a three-dimensional exploded view and a side view of the display device 1 of this embodiment, respectively. The display device 1 of this embodiment preferably includes a display panel 11, a composite back plate 12, and a support frame 124 sandwiched therebetween. Generally speaking, the display panel 11 includes two substrates (not shown) and a display medium layer (not shown) sandwiched between the two substrates (not shown). The display dielectric layer (not shown) includes a non-self-luminous material (for example, liquid crystal, electrowetting, electrophoresis, or other suitable materials), a self-luminous material (for example, an inorganic light-emitting material, an organic light-emitting material, or other suitable materials). ), Or other suitable materials, or a combination of at least one of the foregoing. The composite back plate 12 is disposed on the back side 112 of the display panel 11, that is, on a side opposite to the display surface 111. The composite back plate 12 has a first plate body 121 and a second plate body 122. The two plate bodies (for example, the first plate body 121 and the second plate body 122) are preferably made of metal (such as steel or other suitable materials). ), Alloy or other suitable materials, but not limited thereto, and the two plates (for example, the first plate 121 and the second plate 122) may be made of substantially the same or different materials.

The first plate body 121 has a first connection surface 1211, which is a surface facing the display panel 11 (for example, the back side 112 of the display panel 11), and the first plate body 121 has a first bending pre-force and is resiliently bent. Specifically, after the first plate body 121 performs the pre-bending operation, the degree of bending will not exceed Passing its drop point, therefore, when the first plate 121 is not affected by other external forces, it can rebound / return to its original state. One surface of the second plate body 122 facing the first connection surface 1211 is defined as a second connection surface 1221. The second connection surface 1221 and the first connection surface 1211 are preferably adhered / adhered through the adhesive layer 123. The adhesive layer 123 may be a double-sided adhesive, a solid / liquid adhesive, or other similar materials. In order to maintain the stability of the connection between the two plates, the Young's coefficient of the adhesive layer 123 is preferably greater than 3 MPa, but is not limited thereto.

In addition, in order to prevent the first plate body 121 and the second plate body 122 from adhering and bending, due to stress, a part of the uneven peeling phenomenon may occur, and the appearance may be similar to a wavy shape. The thickness (h1 and h2) ratio of the first plate body 121 and the second plate body 122 is preferably designed to be between 0.43 and 2.33, for example: (h1 / h2) = 0.43 ~ 2.33, no unit.

Please refer to FIGS. 3 and 4. In this embodiment, the first plate body 121 and the second plate body 122 are pre-curved by using a simple bending jig. After that, the first connection surface 1211 of the first plate body 121 and the second connection surface 1221 of the second plate body 122 are bonded / adhered by using the adhesive layer 123. It should be noted that, in this embodiment, the jig is only used to assist in bending, and not the two plates are bent and formed. In other words, the two plates are maintained in a bent state mainly through the adhesive layer 123. When the two plates are removed from the jig, the two plates will still remain bent. However, once the adhesive layer 123 is removed, the two plates are restored to the original planar plate shape (before bending). In this embodiment, to achieve this purpose, the following relationship can be used as the basis for curvature control: D _sp = ρ _sp [1-cos (L / 2ρ _sp )]. Among them, D _sp is the rebound amount of the plate (unit: MPa), ρ _sp is the radius of curvature of the plate (unit: mm), and L represents the length (unit: mm) of the plate when it is flattened. Specifically, the basis of curvature control is based on the standard that each plate does not exceed its own drop point.

According to this, after the first plate body 121 and the second plate body 122 are pre-bent, the first plate body 121 has a first bending pre-force to be resiliently bent, and the second plate body 122 also has a second bending pre-force. and Responsively bends corresponding to the first plate body 121. Based on the curvature control design of this embodiment, the connection internal force (or called the connection force) of the first connection surface 1211 and the second connection surface 1221, for example, the first connection surface 1211, the second connection surface 1221, and the adhesive layer 123 are respectively The tension between the first bending force and the first bending force and the second bending force can be balanced with each other, thereby maintaining the bending degree of the first plate body 121 and the second plate body 122. In addition, the overall strength is increased. In the foregoing embodiment, the adhesive layer 123 is shown in different thicknesses in the exploded view of FIG. 3 and the assembly view of FIG. 4.

As shown in FIG. 5, the adhesive layer 123 is affected by the directions of the tensile forces F1 and F2 of the first connecting surface 1211 and the second connecting surface 1221. The stresses F1 and F2 are at angles Θ1 and Θ2 which are not orthogonal to the first connection surface 1211 and the second connection surface 1221, respectively.

Please continue to refer to FIGS. 1 to 4. In order to enhance the overall strength and supportability, the display device 1 has a design of a support frame 124. The supporting frame 124 may be a plastic frame or a metal frame, and is not particularly limited. The support frame 124 has a top 1242 on one side facing the display panel 11 (eg, the back side 112 of the display panel 11), and the support frame 124 has a bottom 1241 on one side facing the composite back plate 12. The top portion 1242 is viewed from the direction of the display panel 11. From a three-dimensional perspective, the top portion 1242 presents a flange structure. The support frame 124 is sandwiched between the display panel 11 and the composite back plate 12. The supporting frame 124 is fixedly attached to at least a part of the periphery (or referred to as an edge) of the composite back plate 12, such as gluing, riveting, welding, or other suitable methods.

The combination of the support frame 124 and the synthetic back plate 12, for example, the second plate body 122 is sandwiched between the first plate body 121 and the support frame 124. To facilitate joining, in the initial state, the second plate body 122 has a second end portion 1222 protruding beyond the first end portion 1212 of the first plate body 121. For example, the length of the long side of the second plate body 122 will be slightly longer than the first The length of the long side of a plate body 121. When the second end portion 1222 of the second plate body 122 is bent in the direction of the display panel 11, it can be connected to the bottom portion 1241 of the support frame 124. Fixing (such as gluing or other similar methods described above), for example, as shown in FIG. 3 or FIG. 4. In the embodiment of FIG. 3 or FIG. 4, after the second end portion 1222 of the second plate body 122 is fixed to the bottom 1241 of the support frame 124, it does not protrude beyond the first plate body 121.

In other embodiments, as shown in FIG. 6, the second end portion 1222 of the second plate body 122 may be directly fixed to the bottom portion 1241 of the support frame 124 without bending, and the second end portion of the second plate body 122 may be fixed. After 1222 is fixedly connected to the bottom 1241 of the supporting frame 124, it may selectively protrude or not protrude beyond the first plate body 121. In this embodiment, the second end portion 1222 of the second plate body 122 is fixed to the bottom 1241 of the support frame 124 and is not protruded outside the first plate body 121 as an example, but is not limited thereto.

In another embodiment, as shown in FIG. 7, after the second end portion 1222 of the second plate body 122 is bent toward the display panel 11 and fixed to the bottom 1241 of the support frame 124, it still protrudes from the first plate. Outside the body 121.

The display panel 11 is curved corresponding to the composite back plate 12. Preferably, the degree of curvature of the display panel 11 is consistent with the degree of curvature of the composite back plate 12. At least a part of the periphery of the display panel 11 is fixed to the top 1242 of the support frame 124 (such as gluing or other similar methods). In practical applications, since the display panel 11 is located outside the top 1242 of the support frame 124 (as opposed to one side of the composite back plate 12), it can provide a narrower frame appearance design. After the display panel 11, the composite back plate 12 and the supporting frame 124 are assembled, as shown in FIGS. 4, 6 and 7, the supporting frame 124 will be formed into a frame. As viewed from a three-dimensional perspective, it roughly looks like a thin box. Specifically, the display panel 11, the support frame 124, and the second plate body 122 are enclosed in a frame structure. The support frame 124 is vertically connected between the display panel 11 and the composite back plate 12, which can further increase the rigidity and strength of the overall structure.

In an embodiment, when the second plate 122 has a light leakage situation, or there is a In the case of defects, the first plate body 121 can be made of a light-opaque material, and can also be used as a shielding member. In another embodiment, since the first plate body 121 and the second plate body 122 are directly adhered through the adhesive layer 123, the first plate body 121 does not have any extra sheet metal structures, such as convex hulls, depressions, or Other similar structures cause unevenness. Therefore, in terms of appearance, the first plate body 121 may be relatively flat or smooth, and may have a beautiful effect.

In other embodiments, the support frame 124 and the second plate body 122 may form a cavity 125 (also referred to as a receiving cavity), and at least one of the following suitable components may be disposed in the cavity 125, such as a backlight module, a heat sink, and the like. Sheet, or other suitable component. In another embodiment, the aforementioned heat sink may be disposed on one side of the first plate body 121 opposite to the display panel 11, but is not limited thereto.

Please refer to FIG. 8 for another embodiment of the present invention. The display device 2 preferably includes a display panel 21, a composite back plate 22, and a support frame 224 sandwiched therebetween. The composite back plate 22 is disposed on the back side 212 of the display panel 21 (for example, on the side opposite to the display surface 211). The composite back plate 22 includes a first plate body 221 and a second plate body 222. Similarly, the two plates (for example, the first plate 221 and the second plate 222) are preferably made of metal (such as steel or other suitable materials), alloy, or other suitable materials, but not This is a limitation, and the two plates (for example, the first plate 221 and the second plate 222) may be made of substantially the same or different materials.

The first plate body 221 has a first connection surface 2211, which is a surface facing the display panel 21 (for example, the back side 212 of the display panel 21), and the first plate body 221 has a first bending prestress and is resiliently bent. Specifically, after the first plate body 221 performs the pre-bending operation, the degree of bending will not exceed its drop point. Therefore, when the first plate body 221 is not affected by other external forces, it can rebound / return to its original state. One surface of the second plate body 222 facing the first connection surface 2211 is defined as a second connection surface 2221. The second connection surface 2221 and the first connection surface 2211 are also preferably adhered / adhered through the adhesive layer 123. Adhesive layer 223 can It is double-sided tape, solid / liquid glue or other similar materials. In order to maintain the pulling stress between the two plates, the Young's coefficient of the adhesive layer 223 is preferably greater than 3 MPa, but is not limited thereto.

In addition, in order to prevent the first plate body 221 and the second plate body 222 from sticking and bending, a partially uneven peeling phenomenon may occur due to stress pulling, and the appearance may be similar to a wavy shape. The thickness (h1 and h2) ratio of the first plate body 221 and the second plate body 222 is preferably designed to be between 0.43 and 2.33, for example: (h1 / h2) = 0.43 ~ 2.33.

Referring to FIGS. 9 and 10, the first plate body 221 and the second plate body 222 are pre-bent using a simple bending jig, and then the first connection surface 2211 and the second plate body 221 of the first plate body 221 are passed through the adhesive layer 223 The second connection surface 2221 of the plate body 222 is bonded / adhered. It should be noted that, in this embodiment, the jig is only used to assist in bending, and not the two plates are bent and formed. In other words, the two plates are maintained in a bent state mainly through the adhesive layer 223. After the two plates are removed from the jig, the two plates will still remain bent. However, once the adhesive layer 223 is removed, the two plates are restored to the original planar plate shape (before bending). In this embodiment, to achieve this purpose, the following relationship can be used as the basis for curvature control: D _sp = ρ _sp [1-cos (L / 2ρ _sp )]. Among them, D _sp is the rebound amount of the plate (unit: MPa), ρ _sp is the radius of curvature of the plate (unit: mm), and L represents the length (unit: mm) of the plate when it is flattened. Specifically, the basis of curvature control is based on the standard that each plate does not exceed its own drop point.

Accordingly, after the first plate body 221 and the second plate body 222 are pre-bent, the first plate body 221 has a first bending pre-force and is resiliently bent, and the second plate body 222 also has a second bending pre-force. Instead, it can be flexibly bent corresponding to the first plate 221. Based on the curvature control design of this embodiment, the internal force (or the connection force) between the first connection surface 2211 and the second connection surface 2221 (eg, the first connection surface 2211, the second connection surface 2221, and the rubber layer 223 are The tension between the first bending force and the first bending force and the second bending force can balance each other, thereby maintaining the bending degree of the first plate body 221 and the second plate body 222. In addition, the overall strength is increased.

Similarly, referring to FIG. 5 and its description, the adhesive layer 223 in this embodiment is affected by the directions of the pulling forces F3 and F4 of the first connecting surface 2211 and the second connecting surface 2221, for example, the adhesive layer 223 and the first connecting surface 2211 Shear stresses F3 and F4 between the second connection surface 2221 and the first connection surface 2211 and the second connection surface 2221 respectively include angles θ3 and θ4 that are not at right angles.

In addition, in order to enhance the overall strength and supportability, the display device 2 also has a design of a support frame 224. The support frame 224 may be a plastic frame or a metal frame, and is not particularly limited. One side of the support frame 224 facing the display panel 21 (for example, the back side of the display panel 21) has a top 2242, and one side of the support frame 224 facing the composite back plate 22 has a bottom 2241. The top portion 2242 is viewed from the direction of the display panel 21. From a three-dimensional perspective, the top portion 2242 presents a flange structure. The support frame 224 is sandwiched between the display panel 21 and the composite back plate 22. The supporting frame 224 is fixedly attached to at least a part of the periphery (or referred to as an edge) of the composite back plate 22, such as gluing, riveting, welding, or other suitable methods.

The combination of the support frame 224 and the composite back plate 22, for example, the second plate 222 is sandwiched between the first plate 221 and the support frame 224. To facilitate joining, in the initial state, the first plate body 221 has a first end portion 2212 protruding beyond the second end portion 2222 of the second plate body 222. For example, the length of the long side of the first plate body 221 will be slightly larger than that of the first plate body 221. The length of the long sides of the two plates 222. When the first end portion 2212 of the first plate body 221 is bent in the direction of the display panel 21, it can be fixed to the bottom 2241 of the support frame 224 (such as gluing or other similar methods described above), for example: 9 or Figure 10. In the embodiment of FIG. 9 or FIG. 10, after the first end portion 2212 of the first plate body 221 is fixed to the bottom 2241 of the support frame 124, it still protrudes beyond the second plate body 221, and the second plate body 222 It can be located in the receiving area formed by the first plate body 221.

In addition, the display panel 21 is curved corresponding to the composite back plate 22. More preferably, The curvature of the display panel 21 corresponds to the curvature of the composite back plate 22. At least a part of the periphery of the display panel 21 is fixed to the top 2242 of the support frame 224 (such as gluing or other similar methods). In actual application, since the display panel 21 is located outside the top 2242 of the support frame 224 (as opposed to one side of the composite back plate 22), it can provide a narrower frame design.

In an embodiment, when the second plate 222 has a light leakage or a defect in the manufacturing process, the first plate 221 may be made of a light-opaque material or used as a shielding member. Furthermore, because the first plate body 221 does not have any extra sheet metal structures, such as convex hulls, depressions, or other structures that cause unevenness, the appearance of the first plate body 221 may be flat or may be relatively flat. Smooth, but can also have a beautiful effect.

Similarly, the support frame 224 is formed as a frame. As viewed from a three-dimensional perspective, it roughly looks like a thin box. Specifically, the display panel 21, the support frame 224, and the second plate 222 are enclosed by a frame.

In other embodiments, the support frame 224 and the second plate 222 may form a cavity 225 (also referred to as a receiving cavity), and at least one of the following suitable components may be disposed in the cavity 225, such as a backlight module, a heat sink, and the like. Sheet, or other suitable component. In another embodiment, the aforementioned heat sink may be disposed on one side of the first plate body 221 opposite to the display panel 21, but is not limited thereto.

In order to make the foregoing display device 1 or 2 more beautiful, the outer surface of the first plate 121 or 221 of the foregoing embodiment (for example, a surface opposite to the first connecting surface (or inner surface) 2211 or 1211) In the above, a decorative plate (not shown) or a shell plate (not shown) can be selectively connected, and still have the effects and advantages described in the foregoing embodiments of the present invention.

Therefore, the display device of the present invention has better curvature control for the back plate, and requires only simple jig assistance in assembly. In addition to providing thinner, narrower bezels, beautiful back Besides design, it can also reduce production costs.

Claims (9)

A display device includes: a display panel; and a composite back plate disposed on the back side of the display panel; wherein the composite back plate has: a first plate body having a first connection surface; wherein the first A plate body has a first bending pre-force to be resiliently bent; and a second plate body has a second connection surface facing the first connection surface and at least partially connected to the first connection surface; wherein, the The second plate body has a second bending pre-force which can resiliently correspond to the bending of the first plate body; wherein the internal force of the connection between the first connection surface and the second connection surface, the first bending pre-force and the The second bending pre-force is balanced to maintain the bending degree of the first plate body and the second plate body. The display device according to claim 1, wherein a thickness ratio of the first plate body to the second plate body is between 0.43 and 2.33. The display device according to claim 1, wherein the synthetic backboard includes an adhesive layer sandwiched between the first connection surface and the second connection surface, and the adhesive layer is connected by the first connection surface and the second connection The directions of the surface tension are respectively at non-right angles with the first connection surface and the second connection surface. The display device according to claim 3, wherein the Young's coefficient of the adhesive layer is greater than 3 MPa. The display device according to claim 1, further comprising a support frame sandwiched between the display panel and the composite back plate; wherein the support frame is fixedly connected to at least a part of the periphery of the composite back plate. The display device according to claim 5, wherein the second plate system is sandwiched between the first plate body and the support frame, and the second plate body has a second end portion protruding from the first plate body. A first end portion is outside; the support frame has a bottom portion facing the second plate body, and the bottom portion is fixedly connected to the second end portion. The display device according to claim 5, wherein the second plate system is sandwiched between the first plate body and the support frame, and the first plate body has a first end protruding from the second plate body. A second end portion is outside; the support frame has a bottom portion facing the first plate body, and the bottom portion is fixedly connected to the first end portion. A display device includes: a display panel having a degree of curvature; and a composite back plate disposed on a back side of the display panel and bent corresponding to the display panel; wherein the composite back plate includes: a first plate A body having a first connecting surface, wherein the first plate body has a first bending pre-force to be resiliently bent; and a second plate body having a second connecting surface facing the first connecting surface and The first connecting surface is at least partially connected; wherein the second plate body has a second bending pre-force and is resiliently bent corresponding to the first plate body; wherein the first plate body and the second plate body The thickness ratio is between 0.43 and 2.33; and wherein the internal force of the connection between the first connection surface and the second connection surface is balanced with the first bending prestress and the second bending prestress to maintain the first plate. Of the body and the second plate body. A display device includes: a display panel having a curvature; a support frame supporting at least a part of a periphery of the display panel; and a composite back plate disposed on a side of the support frame facing away from the display panel, And is curved corresponding to the display panel; wherein the composite back plate has: a first plate body having a first connection surface, wherein the first plate body has a first bending pre-force to be resiliently bent; and A second plate body having a second connection surface facing the first connection surface and at least partially connected to the first connection surface; wherein the second plate body has a second bending pre-force and resiliently corresponds to The first plate body is bent; wherein one of the first plate body or the second plate body has one end protruding beyond the other; the support frame is fixedly connected to the end; and wherein the first A connection internal force between a connection surface and the second connection surface is balanced with the first bending pre-force and the second bending pre-force to maintain the bending degree of the first plate body and the second plate body.