CN114495725A

CN114495725A - Flexible display device

Info

Publication number: CN114495725A
Application number: CN202210246923.XA
Authority: CN
Inventors: 石钰; 金武谦
Original assignee: Wuhan China Star Optoelectronics Semiconductor Display Technology Co Ltd
Current assignee: Wuhan China Star Optoelectronics Semiconductor Display Technology Co Ltd
Priority date: 2022-03-14
Filing date: 2022-03-14
Publication date: 2022-05-13

Abstract

The invention discloses a flexible display device. The flexible display device comprises a flexible display panel, a metal supporting layer, a main battery, a thin film battery and an equipment main board; the main battery is electrically connected with the equipment main board, and the equipment main board is electrically connected with the flexible display panel; the flexible display panel and the thin film battery are positioned on the metal supporting layer; the thin film battery is attached to the bottom of the flexible display panel and is bent or/and stretched synchronously with the flexible display panel. According to the invention, the back plate supporting layer below the flexible display panel in the prior art is replaced by the thin film battery, the thin film battery can be used as a secondary battery to provide a power supply for the electronic equipment, and can also provide a certain support for the flexible display panel, so that under the condition of keeping the internal structural space of the electronic equipment unchanged, the electric quantity storage and the cruising ability of the electronic equipment are improved.

Description

Flexible display device

Technical Field

The invention relates to the technical field of display, in particular to a flexible display device.

Background

The flexible display screen can bring the form change of electronic equipment such as smart phones, notebook computers and the like. As shown in fig. 1, the bottom of the conventional flexible display panel is usually provided with a back plate support layer and a metal support layer, wherein the back plate support layer can enhance the shock resistance of the display panel, and the metal support layer can enable the display panel to provide strong support when the display panel is bent and stretched.

The flexible display panel is generally bent and extended by a rotating shaft, a motor, and the like. However, the rotating shaft, the motor and other devices occupy a large amount of space of the mobile phone, the volume of the mobile phone battery is compressed, the capacity of the mobile phone battery is reduced, and the cruising performance of the mobile phone is seriously reduced.

Disclosure of Invention

Based on the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a flexible display device, which can ensure the endurance of the device while satisfying the requirement of bending or stretching of the display panel.

In order to achieve the above object, the present invention provides a flexible display device, which includes a flexible display panel, a metal supporting layer, a main battery, a thin film battery, and a device main board; the main battery is electrically connected with the equipment main board, and the equipment main board is electrically connected with the flexible display panel; the flexible display panel and the thin film battery are positioned on the metal supporting layer; the thin film battery is attached to the bottom of the flexible display panel and is bent or/and stretched synchronously with the flexible display panel.

Optionally, only one end of the flexible display panel is flexible, the thin film battery comprises a display area and a non-display area, and the non-display area comprises a curved portion or/and a planar portion.

Optionally, after the flexible display panel is shortened, one end of the curved portion is connected to the display area, and the other end of the curved portion is connected to the planar portion, and the planar portion is parallel to the display area.

Optionally, the radius of curvature of the curved portion is 1.5mm to 6 mm.

Optionally, the flexible display panel is shortened and the curved portion is curled inward.

Optionally, the radius of curvature of the curved portion is 1mm to 6 mm.

Optionally, after the flexible display panel is shortened, the bending portion includes a first bending portion and a second bending portion, and the bending direction of the first bending portion is different from that of the second bending portion.

Optionally, the thin film battery has a length of expansion of 1cm to 10 cm.

Optionally, both ends of the flexible display panel are flexible, the flexible length of each end of the thin film battery is 1cm to 8cm, and the curvature radius of the bending area of the thin film battery is 1mm to 10 mm.

Optionally, the length of the thin film battery is less than or equal to the length of the flexible display panel.

Compared with the prior art, the invention has the beneficial effects that: the flexible display device comprises a flexible display panel, a metal supporting layer, a main battery, a thin film battery and an equipment main board; the main battery is electrically connected with the equipment main board, and the equipment main board is electrically connected with the flexible display panel; the flexible display panel and the thin film battery are positioned on the metal supporting layer; the thin film battery is attached to the bottom of the flexible display panel and is bent or/and stretched synchronously with the flexible display panel. According to the invention, the back plate supporting layer below the flexible display panel in the prior art is replaced by the thin film battery, the thin film battery can be used as a secondary battery to provide a power supply for the electronic equipment, and can also provide a certain support for the flexible display panel, so that under the condition of keeping the internal structural space of the electronic equipment unchanged, the electric quantity storage and the cruising ability of the electronic equipment are improved.

Drawings

In order to illustrate the embodiments or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the invention, and it is obvious for a person skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a first schematic structural diagram of a flexible display device according to an embodiment of the present invention;

FIG. 2 is a schematic of the structure of a prior art flexible display device;

FIG. 3 is a first schematic structural diagram of a thin film battery according to an embodiment of the present invention;

FIG. 4 is a second schematic structural diagram of a thin film battery according to an embodiment of the present invention;

FIG. 5 is a third schematic structural diagram of a thin film battery according to an embodiment of the present invention;

FIG. 6 is a fourth schematic structural diagram of a thin film battery according to an embodiment of the present invention;

FIG. 7 is a second schematic structural diagram of a flexible display device according to an embodiment of the present invention;

FIG. 8 is a third schematic structural diagram of a flexible display device according to an embodiment of the present invention;

fig. 9 is a fourth schematic structural diagram of a flexible display device according to an embodiment of the present invention.

Detailed Description

The following description of the various embodiments refers to the accompanying drawings, which are included to illustrate specific embodiments in which the invention may be practiced. In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations or positional relationships based on those shown in the drawings, merely for convenience of description and simplification of the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

An embodiment of the present invention provides a flexible display device, as shown in fig. 1, including a flexible display panel 200, a metal supporting layer 300, a main battery (not shown), a thin film battery 400, and a device main board (not shown); the main battery is electrically connected with the device main board, and the device main board is electrically connected with the flexible display panel 200; the flexible display panel 200 and the thin film battery 400 are positioned on the metal support layer 300; the thin film battery 400 is attached to the bottom of the flexible display panel 200, and bends or/and stretches with the flexible display panel 200.

In the prior art, as shown in fig. 2, the structure layers of the flexible display device are sequentially from top to bottom: a screen protection layer 101, an adhesive layer 102, an ultra-thin glass layer 103 or a transparent polyimide layer 104, an adhesive layer 102, a polarizer 105, an adhesive layer 102, a touch dot matrix layer 106, a flexible display panel 200, an adhesive layer 102, a back panel support layer 500, a foam rubber layer 107, and a metal support layer 300.

In this embodiment, the backplane support layer 500 below the flexible display panel 200 in the prior art is replaced with the thin film battery 400, and the thin film battery 400 can serve as a secondary battery to provide a power supply for the electronic device, and can also provide a certain support for the flexible display panel 200, so that under the condition that the internal structural space of the electronic device is not changed, the power storage and the cruising ability of the electronic device are improved.

In one embodiment, as shown in fig. 3, the flexible display panel 200 is extended and contracted at only one end, the thin film battery 400 includes a display region 410 and a non-display region 420, and the non-display region 420 includes a curved portion 421 or/and a flat portion 422. For example, the right end of the flexible display panel 200 may be extended or retracted, and when the flexible display panel 200 is extended, the thin film battery 400 is also extended, so that the area of the display area is increased, and the display area of the flexible display panel 200 may be increased; when the flexible display panel 200 is shortened, the thin film battery 400 is also shortened, the area of the display area is reduced, the whole area of the flexible display panel 200 is reduced, the size of the flexible display device is also reduced, and the flexible display device is beneficial to a user to store.

In one embodiment, the thin film battery 400 may be attached to the flexible display panel 200 by an OCA (optical Clear Adhesive) or a PSA (Pressure Sensitive Adhesive).

In one embodiment, the thin film battery 400 may be a flexible polymer lithium ion battery, or may be other flexible batteries, such as a zinc ion battery, a magnesium ion battery, and the like.

In one embodiment, thin film battery 400 is between 50um and 500um thick. Thus, the thin film battery 400 can have a certain battery capacity, and meanwhile, a certain supporting force is provided for the flexible display panel 200, and the impact resistance of the flexible display panel 200 is improved.

In one embodiment, as shown in fig. 4, after the flexible display panel 200 is shortened, one end of the curved portion 421 is connected to the display area 410, the other end is connected to the flat portion 422, and the flat portion 422 is parallel to the display area 410. Therefore, the space utilization rate of the flexible display panel 200 and the thin film battery 400 can be improved, and the flexible display panel 200 and the thin film battery 400 can be lengthened.

In this embodiment, the expansion and contraction and bending of the thin film battery 400 and the flexible display panel 200 are synchronized. This allows a good bonding of the thin film battery 400 to the flexible display panel 200 while facilitating the manufacturing process.

In one embodiment, the flexible display panel 200 and the thin film battery 400 have a telescopic length of 1cm to 10 cm. In this embodiment, the flexible length of the flexible display panel 200 and the thin film battery 400 may be selected to be 5cm to 8 cm. This may provide a reasonable balance between production costs and flexibility of the flexible display panel 200.

In the above structure, the radius of curvature of the curved portion 421 is 1.5mm to 6 mm. This allows the thickness of the flexible display device to be kept within a reasonable range, and avoids over-bending, which may damage the flexible display panel 200.

In one embodiment, the bending portion 421 is curled inward after the flexible display panel 200 is shortened. Thus, the flexible display panel 200 and the thin film battery 400 can have a longer expansion range, and the space occupied by the non-display area in the flexible display panel 200 and the thin film battery 400 is saved.

In the above structure, the radius of curvature of the curved portion 421 is 1mm to 6 mm. This can keep the thickness of the flexible display device within a reasonable range, and avoid the excessive curvature, which may damage the flexible display panel 200.

In one embodiment, as shown in fig. 5, after the flexible display panel 200 is shortened, the bending portion 421 includes a first bending portion 4211 and a second bending portion 4212, and the first bending portion 4211 and the second bending portion 4212 are bent in different directions. Specifically, one end of the first flexure 4211 is connected to the display region 410, and the other end is connected to one end of the second flexure 4212. For example, the first bending portion 4211 is bent inward, the second bending portion 4212 is bent outward, and the second bending portion 421 is closer to the thin film battery 400 than the first bending portion 421. This allows a large receiving space for the non-display area of the flexible display panel 200 and the thin film battery 400 without affecting the overall structural space of the flexible display device.

In one embodiment, as shown in fig. 6, both ends of the flexible display panel 200 are stretched, each end of the thin film battery 400 has a stretching length of 1cm to 8cm, and the curvature radius of the bending region 421 of the thin film battery 400 is 1mm to 10 mm. Specifically, both ends of the flexible display panel 200 and the thin film battery 400 can be extended and retracted, so that the extension and retraction lengths of the flexible display panel 200 and the thin film battery 400 can be further increased in a limited space.

In one embodiment, the length of the thin film battery 400 is less than or equal to the length of the flexible display panel 200. This may allow the lengths or areas of the thin film battery 400 and the flexible display panel 200 to be adapted to each other.

In this embodiment, the thin film battery 400 is used to replace the original back plate supporting layer 500, so that the battery design of the flexible display device can be optimized, the internal space of the electronic device can be saved, and the cruising ability of the electronic device can be increased.

In one embodiment, as shown in fig. 7, the structure of the flexible display device is as follows from top to bottom: a flexible display panel 200, an adhesive layer 102, a thin film battery 400, an adhesive layer 102, a rubber foam layer 107, an adhesive layer 102, and a metal support layer 300.

In one embodiment, to increase the support of the flexible display panel 200, a back plate support layer 500 may be added below the thin film battery 400. As shown in fig. 8, the structure of the flexible display device of this embodiment may be as follows, from top to bottom: a flexible display panel 200, an adhesive layer 102, a thin film battery 400, an adhesive layer 102, a backplane support layer 500, an adhesive layer 102, a rubber foam layer 107, an adhesive layer 102, and a metal support layer 300.

In one embodiment, a back plate support layer 500 may be added above the thin film battery 400. As shown in fig. 9, the display panel and the under-screen structure may be as follows, from top to bottom: a flexible display panel 200, an adhesive layer 102, a backplane support layer 500, an adhesive layer 102, a thin film battery 400, an adhesive layer 102, a rubber foam layer 107, an adhesive layer 102, and a metal support layer 300.

It is understood that the thin film battery 400 and the back plate may be supported in two or more than two according to a specific structural design of the flexible display device.

In an embodiment, the metal supporting layer 300 may be a patterned stainless steel layer, and the bending region may be a hollow pattern, so that the stainless steel layer may have a larger bending curvature, and the bending portion is prevented from being broken due to an excessive stress when the stainless steel layer is bent.

In one embodiment, the hollow pattern may be one or more of a rectangle, a parallelogram, or a trapezoid. Other regular or irregular polygons are also possible. The hollow pattern can also be in a strip shape or a wave shape.

In one embodiment, the flexible display panel 200 includes a driving circuit layer, a light emitting functional layer, and an encapsulation layer.

The driving circuit layer comprises a flexible substrate and a TFT (thin film transistor) layer positioned on the surface of the flexible substrate, wherein the flexible substrate comprises a first organic layer and an inorganic layer which are sequentially laminated; the first organic layer is a whole-surface film layer, the inorganic layer is a patterned structure, the whole-surface film layer is a uniform and seamless whole film, the patterned structure can be an interval concave-convex structure, or a gap is arranged between the first organic layer and the inorganic layer, when the film is deformed due to bending, the bending stress can be released, the stress borne by the inorganic layer is reduced, and then the inorganic layer is prevented from being broken or stripped from the first organic layer, so that the flexibility of the flexible substrate is enhanced, and the service life of the flexible substrate is prolonged.

The driving circuit layer is positioned on the surface of the flexible substrate and comprises a buffer layer, a driving layer and an ITO layer which are stacked from bottom TO top; the buffer layer is formed on the surface of the flexible substrate, the driving layer is formed on the surface of the buffer layer and comprises a plurality of driving thin film transistors, and each driving thin film transistor at least comprises a grid electrode, a grid electrode insulating layer, an active layer and a source drain layer; the grid insulating layer is formed on the grid electrode layer, the active layer is formed on the grid insulating layer and is arranged in an insulating mode with the grid electrode layer, the source drain electrode layers are arranged on two sides of the active layer and comprise a source electrode and a drain electrode, and the source electrode and the drain electrode are electrically connected with the corresponding positions of the active layer respectively.

The light-emitting function layer is positioned on the surface of the driving circuit layer, and is of a single-layer device structure, a double-layer device structure, a three-layer device structure or a multi-layer device structure. The packaging layer is generally an inorganic/organic/inorganic multilayer film stacked structure and is positioned on the surface of the light-emitting function layer to protect a light-emitting device in the light-emitting function layer from being corroded by water vapor, so that the display life of the display panel is prolonged.

The embodiment of the invention also provides a preparation method of the flexible display device, which comprises the following steps:

(1) and preparing the flexible display panel.

The method specifically comprises the steps of preparing an array substrate on a flexible substrate, wherein the material of the flexible substrate comprises polyimide; then sequentially forming an anode, a hole injection layer, a hole transport layer, a luminescent layer, an electron transport layer, an electron injection layer and a cathode on the array substrate; and then performing thin film encapsulation to form an encapsulation layer, and finally obtaining the flexible display panel.

In one embodiment, the encapsulation layer is an organic layer formed on the inorganic layer, an inorganic layer formed on the organic layer, an inorganic/organic/inorganic three-layer structure, or a multi-layer structure; wherein the encapsulation layer can be formed by depositing inorganic and organic substances by means of CVD (chemical vapor deposition), sputtering, ALD (atomic deposition), vacuum evaporation, JP (ink jet printing) and the like.

(2) And arranging a touch control functional component in the light emergent direction of the flexible display panel.

The touch functional component is an external touch functional component, COP (cyclic olefin polymer) or PET (polyethylene terephthalate) is used as a substrate, and ITO (indium tin oxide) is deposited on the substrate and patterned to obtain the touch functional component. Specifically, the touch functional component is an embedded touch functional component, and ITO or metal is directly deposited on an encapsulation layer of the flexible display panel to form the touch functional component; the patterned structure of the touch functional component sensor can be prepared by PVD (physical vapor deposition), CVD (chemical vapor deposition) and the like, or by metal mesh technology, to obtain the touch functional component.

In one embodiment, the touch functional member is an in-cell touch functional member, and the touch functional member may be formed by coating nano silver wires on the flexible display panel and patterning the nano silver wires, or formed by directly coating the nano silver wires on the polarizer and patterning the nano silver wires.

In an embodiment, the polarizing member and the hardening layer may be formed on the flexible layer sequentially, and then the silver nanowires are coated on the back surface of the flexible layer and patterned to form the touch functional member.

(3) And arranging a polarization component in the direction of the touch functional component far away from the flexible display panel.

Wherein, the polarizing component includes CF (color filter) and BM (black matrix), and the preparation process of the polarizing component includes: and depositing CF and BM on the touch functional component, namely depositing CF corresponding to the color of RGB (red, green and blue) pixels, filling BM between the CF, and finally obtaining the polarizing component.

(4) And arranging a protective cover plate.

(5) And (5) laminating the thin film battery.

In one embodiment, the polarizing member and the protective cover plate may be integrated to form the polarizing protective member, so that the thickness of the polarizing protective member is 70-120 μm, then the out-hanging touch functional member is formed by depositing ITO on COP or PET, so that the thickness of the touch functional member is 50-100 μm, and finally the polarizing protective member, the touch functional member, the flexible display panel and the back plate are attached and connected through an adhesive, so that the thickness of the obtained flexible display device is less than 400 μm, and the thickness of the flexible display device is reduced.

The manufacturing method of the polarized light protection member comprises the following steps: CPI (colorless polyimide) is selected as a flexible layer, and then a hardened layer is formed on the surface of the flexible layer, wherein the hardened layer is formed by a preparation method comprising coating, thermal curing and UV (ultraviolet) curing, and then a polarizing layer is prepared on the back of the flexible layer, and finally the polarizing protection member is obtained.

On the basis of the above embodiments, the out-cell touch functional member can be changed into an in-cell touch functional member, ITO can be deposited on the flexible display panel and patterned to form the touch functional member, or nano silver wires can be coated on the polarization member and patterned to form the touch functional member, and the thickness of the obtained flexible display device is less than 300 μm, thereby further reducing the thickness of the flexible display device.

On the basis of the above embodiment, the flexible layer in the protective cover plate can be removed, and the protective cover plate, the polarizing member, the touch functional member, and the flexible display panel are integrally arranged, so that the thickness of the obtained flexible display device is less than 200 μm, and the thickness of the flexible display device is further reduced.

On the basis of the above embodiment, the back plate may be removed, the polarizing member may be formed on the touch functional member, the CFs of the corresponding colors are formed above the corresponding RGB pixels, and the BM is formed between the CFs to obtain the polarizing member, and the thickness of the flexible display device obtained finally is less than 100 μm, which further reduces the thickness of the flexible display device.

Through the steps of the method, the flexible display device with smaller thickness can be obtained, more space can be provided for the arrangement of the thin film battery 400, and the cruising ability of the electronic equipment is further improved.

In this embodiment, the thin film battery 400 is used to replace the backplate supporting layer 500 below the display panel in the prior art, and the thin film battery 400 can be used as a secondary battery to provide a power supply for the electronic device, and can also provide a certain support for the display panel, so that the electric quantity storage and the cruising ability of the electronic device are improved under the condition of keeping the internal structure space of the electronic device unchanged.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A flexible display device is characterized by comprising a flexible display panel, a metal supporting layer, a main battery, a thin film battery and an equipment main board; the main battery is electrically connected with the equipment main board, and the equipment main board is electrically connected with the flexible display panel; the flexible display panel and the thin film battery are positioned on the metal supporting layer; the thin film battery is attached to the bottom of the flexible display panel and is bent or/and stretched synchronously with the flexible display panel.

2. The flexible display device according to claim 1, wherein the flexible display panel is extended and contracted at only one end, the thin film battery comprises a display region and a non-display region, and the non-display region comprises a curved portion or/and a flat portion.

3. The flexible display device according to claim 2, wherein the curved portion is connected to the display area at one end and to the flat portion at the other end after the flexible display panel is shortened, and the flat portion is parallel to the display area.

4. A flexible display device according to claim 3, wherein the radius of curvature of the curved portion is 1.5mm to 6 mm.

5. The flexible display device of claim 2, wherein the curved portion curls inward after the flexible display panel is foreshortened.

6. The flexible display device of claim 5, wherein the curved portion has a radius of curvature of 1mm to 6 mm.

7. The flexible display device of claim 2, wherein the flexible display panel, after being shortened, the curved portion comprises a first curved portion and a second curved portion, and the first curved portion and the second curved portion have different curved directions.

8. A flexible display device according to any of claims 2 to 7, wherein the thin film battery has a telescopic length of 1cm to 10 cm.

9. The flexible display device according to claim 1, wherein both ends of the flexible display panel are extended and contracted, each end of the thin film battery has an extension and contraction length of 1cm to 8cm, and a curvature radius of a portion of the thin film battery playing the bending area is 1mm to 10 mm.

10. The flexible display device of claim 1, wherein the length of the thin film battery is less than or equal to the length of the flexible display panel.