JP6590490B2 - Display device - Google Patents

Description

One embodiment of the present invention relates to an object, a method, or a manufacturing method. Alternatively, one embodiment of the present invention relates to a process, a machine, a manufacture, or a composition (composition of matter). In particular, one embodiment of the present invention relates to, for example, a semiconductor device, a display device, a light-emitting device, a power storage device, a driving method thereof, or a manufacturing method thereof. In particular, one embodiment of the present invention relates to a display device.

The social infrastructure for information transmission means is substantial. As a result, diverse and abundant information can be acquired or transmitted not only at work and at home but also on the go.

A display device having a large screen capable of listing and displaying a large amount of information is suitable for an information terminal device.

In addition, portable information terminal devices that can acquire information on the go have been actively developed. It is important that it is easy to carry when used on the go. It is very convenient that the size of the information terminal device and the size of the display area can be changed according to the usage.

Portable information terminal devices are often used outdoors, and unexpected force may be applied to portable information terminal devices when dropped.

As an example of a display device that can withstand a force applied from the outside and is not easily destroyed, a configuration in which adhesion between a structure that separates a light emitting layer and a second electrode layer is improved is known (Patent Document 1). .

JP 2012-190794 A

One embodiment of the present invention has been made under such a technical background. Therefore, an object is to provide a novel display device that can be folded and has excellent portability. Another object is to provide a novel display device that can display a large seamless screen. Another object is to provide a novel display device that is highly resistant to an external physical force when folded or used with a large screen.

Note that the description of these problems does not disturb the existence of other problems. Note that one embodiment of the present invention does not have to solve all of these problems. Issues other than these will be apparent from the description of the specification, drawings, claims, etc., and other issues can be extracted from the descriptions of the specification, drawings, claims, etc. It is.

One embodiment of the present invention is a display device including a first housing, a display panel, and a first layer. The first housing houses the display panel, and the display panel has flexibility. In addition, the first layer has flexibility and is transmissive to visible light, and at least a part of the first layer is in both the expanded state and the folded state of the display device. The display surface of the display device that is located on the display surface of the display panel and is folded is a display device that includes a display region and a region that transmits visible light.

Another embodiment of the present invention is a display device including a first housing, a display panel, and a first layer. The first housing stores the display panel, and the display panel is flexible. The first layer has flexibility and is transmissive to visible light, and the first layer is positioned on the display surface of the display panel when the display device is deployed. In addition, the display device can fold the first casing and the first layer independently of each other. In particular, it is preferable that the first housing can be folded before the first layer when it is folded, and then the first layer can be folded so as to cover the first housing.

It is preferable that the display device having each configuration described above can be folded so that a part of the display surface of the display panel can be seen from the outside.

The display device having each configuration described above preferably includes a second housing, and the second housing houses the first layer.

It is preferable that the first layer has a larger radius of curvature when the display device having the above structure is folded than the display panel.

The display device having the above-described configuration includes the first layer and the second housing, so that the display panel does not receive physical force directly from the outside even when the display device is expanded or folded. .

The display device having each configuration described above preferably includes a touch sensor in the first layer.

The display device having the above-described configuration preferably has an antireflection layer on at least one of the surfaces of the first layer and the display panel facing each other.

By providing the antireflection function, interference unevenness does not occur even when the distance between the first layer and the display panel is distributed.

In the display device having the above-described configurations, it is preferable that the first casing and the first layer can be removed. Alternatively, the first housing and the second layer may be removable. As a result, if one of them breaks, only the broken one can be replaced, and the cost of repair or the like can be reduced.

There is a high possibility that the first layer and the second housing that receive physical force from the outside cannot be used, but the first layer and the second housing can be made cheaper than the display panel. It is possible to repair cheaply by having a replacement function.

The first layer is preferably larger in thickness than the display panel. The thicker the first layer, the higher the resistance of the display device to physical forces. In one embodiment of the present invention, since the radius of curvature of the first layer can be set larger than that of the display panel, there is an advantage that the thickness of the first layer is not limited as much as that of the display panel.

Note that in this specification, a display device refers to an image display device. In addition, a connector such as a flexible printed circuit (FPC) or a TCP (Tape Carrier Package) attached to a display device, a module provided with a printed wiring board at the end of TCP, or a substrate on which a light emitting element is formed is COG. It is assumed that a module in which an IC (integrated circuit) is directly mounted by the (Chip On Glass) method is also included in the display device.

According to one embodiment of the present invention, a novel display device that can be folded and has excellent portability can be provided. Alternatively, a novel display device that can display on a large seamless screen can be provided. Further, it is possible to provide a novel display device that is highly resistant to an external physical force when folded or widened to use a large screen.

4A and 4B illustrate a state where a display device according to an embodiment is developed. 4A and 4B illustrate a state in which only the display panel of the display device according to the embodiment is folded. 10A and 10B illustrate a state in which a display device according to an embodiment is folded. 4A and 4B each illustrate a structure of a display panel of a display device according to an embodiment.

<Examples of problems that one embodiment of the present invention can solve>
A flexible display panel in which a display element or the like is provided on a flexible substrate is known.

In order to bend the flexible display panel with a small radius of curvature, the film thickness and hardness of the display panel are limited, and the physical strength of the display panel may be weakened.

When a physical force is directly applied to a highly flexible display panel, there arises a problem that the functional film and functional elements of the display panel cannot be protected. On the other hand, when a functional film having high hardness is provided on the display panel, there arises a problem that a bendable radius of curvature becomes large.

<One Embodiment of the Present Invention>
In the embodiment described below, the display panel is prevented from receiving physical force directly from the outside by a housing having a cover film, even when it is expanded and displayed on a large screen or when it is folded. One embodiment of the present invention created by focusing on the above configuration is included.

A display device of one embodiment of the present invention includes a first housing, a second housing, a display panel, and a cover film. The first housing houses the display panel. The second housing stores a cover film. The display panel has flexibility. The cover film has flexibility and transparency to visible light.

In one embodiment of the present invention, in both the expanded state and the folded state of the display device, at least a part of the cover film is located on the display surface of the display panel, and the display surface of the folded display device is It is preferable to have a display region and a region that transmits visible light.

Alternatively, in one embodiment of the present invention, in a state where the display device is unfolded, the cover film is positioned on the display surface of the display panel, and the first casing is folded before the second casing when folded. Preferably, the second housing can then be folded so as to cover the first housing.

It is preferable that the display device having each configuration described above can be folded so that a part of the display surface of the display panel can be seen from the outside.

The display device having each configuration described above preferably includes a second housing, and the second housing houses the first layer.

It is preferable that the first layer has a larger radius of curvature when the display device having the above structure is folded than the display panel. In addition, it is preferable that the thickness of the first layer is larger than that of the display panel.

In the above configuration, by having the cover film and the second housing, the display panel does not receive physical force directly from the outside even when the display device is expanded or folded.

As a result, a novel display device that can be folded and has excellent portability can be provided. Alternatively, a novel display device that can display information or the like on a large seamless screen can be provided. Further, it is possible to provide a novel display device that is highly resistant to an external physical force when folded or widened to use a large screen.

Embodiments will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it is easily understood by those skilled in the art that modes and details can be variously changed without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments below. Note that in structures of the invention described below, the same portions or portions having similar functions are denoted by the same reference numerals in different drawings, and description thereof is not repeated.

(Embodiment 1)
In this embodiment, the structure of the display device of one embodiment of the present invention will be described with reference to FIGS.

FIGS. 1A to 3A are top views of a display device of one embodiment of the present invention, and FIGS. 1B to 3B correspond to FIGS. It is a side view of A).

1A and 1B are diagrams illustrating a state where the display device of one embodiment of the present invention is developed. The display device of one embodiment of the present invention can be displayed on a large seamless screen by being unfolded.

As shown in the enlarged view of the portion surrounded by the alternate long and short dash line in FIG. 1B, the cover film 503 is preferably thicker than the display panel 501. Note that although an example in which the thickness of the first housing 502 and the second housing 504 are equal is described in this embodiment, one embodiment of the present invention is not limited thereto.

2A and 2B illustrate a state in which only the display panel of the display device of one embodiment of the present invention is folded.

3A and 3B illustrate a state in which the display device of one embodiment of the present invention is folded. By folding the display device of one embodiment of the present invention, portability can be improved.

A display device 500 described in this embodiment includes a folding mechanism 550, a display panel 501, a first housing 502, a cover film 503, and a second housing 504. The first housing 502 houses the display panel 501. The display panel 501 includes a display area 505 that can display information and the like. The second housing 504 stores the cover film 503. By folding the display panel 501, the display device 500 may be provided with a region 506 that transmits only visible light and includes only the cover film 503.

When the display device is deployed, the display panel 501 has a structure in which a cover film 503 is provided on the display surface side, and the display panel 501 can reduce damage due to an external physical force ( (See FIG. 1).

Each of the first housing 502 and the second housing 504 includes a folding mechanism 550, and only the first housing 502 can be folded. At that time, a part of the display panel 501 is folded inside the first housing 502 and a part of the display surface is inside. The inside place can reduce physical damage from the outside (see FIG. 2).

After the first housing 502 is folded, the second housing 504 is folded so as to cover the first housing 502, so that the display panel 501 can be physically exposed from the outside by the first housing 502 or the cover film 503. Damage can be reduced (see FIG. 3). Note that the second housing 504 need not cover the entire first housing 502.

As a result, a novel display device 500 that is foldable and excellent in portability can be provided. Alternatively, a novel display device 500 that can display on a large seamless screen can be provided. Further, it is possible to provide a novel display device that is highly resistant to an external physical force when folded or widened to use a large screen.

When the display device is folded, the first housing and the second housing are folded separately. At that time, the second casing is folded with a larger radius of curvature than the first casing. Therefore, the cover film installed in the second housing does not require bending resistance as much as the display panel installed in the first housing.

In the present embodiment, the case where the display panel is folded in three is shown as an example, but the present invention is not limited to this. As long as the display area can be viewed from the outside when folded, it is an embodiment of the present invention regardless of how it is folded.

The individual elements included in the display device of one embodiment of the present invention are described below.

《Cover film》
The cover film 503 needs to reduce external damage to the display panel 501. For this reason, it is necessary that the hardness is high enough to prevent distortion and the like when external force is applied. And if hardness is high, generation | occurrence | production of the flaw etc. which degrade display quality can be suppressed. Further, since it is necessary to emit light from the display panel to the outside, it is necessary to have transparency to visible light.

When the hardness is increased, the bending characteristics are deteriorated. However, as shown in FIG. 3, the cover film 503 is folded with a larger radius of curvature than the display panel 501. Therefore, in one embodiment of the present invention, sufficient hardness and bending characteristics are obtained. Obtainable.

Note that the cover film 503 may be provided with a touch sensor function. Since the cover film 503 and the display panel 501 have different housings, a sufficient distance can be obtained and the display panel 501 is not affected by the parasitic capacitance of the display panel. Therefore, even a capacitive touch sensor can have high sensitivity.

Since the first housing 502 and the second housing 504 can be folded separately, the distance between the cover film 503 and the display panel 501 can be easily distributed in the plane. When interference fringes due to the distribution are generated, the display quality is degraded. Therefore, it is preferable to perform a non-reflection treatment on the display panel side of the cover film 503. As the antireflection treatment, a moth-eye structure having a low wavelength dependency is preferable.

The antireflection treatment may be performed on the display surface side of the display panel 501. Moreover, you may go to both the cover film 503 and the display panel 501. By performing the non-reflection treatment, it is possible to increase the light extraction efficiency as well as to suppress the interference fringes.

As a material for the cover film 503, various plastics having transparency to visible light can be used. For example, polyimide (PI), aramid, polyethylene terephthalate (PET), polyethersulfone (PES), polyethylene naphthalate (PEN), polycarbonate (PC), nylon, polyetheretherketone (PEEK), polysulfone (PSF), polysulfone Plastics such as etherimide (PEI), polyarylate (PAR), polybutylene terephthalate (PBT), and silicone resin can be used. In particular, it is preferable to use inexpensive PET or PEN. Since high bending characteristics are not required, the display panel 501 can be made sufficiently thicker. In general, a flexible display panel has a thickness of 100 μm or less, but the cover film 503 can have a thickness of 100 μm or more and less than 1000 μm, preferably 200 μm or more and 400 μm or less.

In order to increase the surface hardness, an inorganic film may be formed on the plastic film. As the inorganic film, a film having high translucency with respect to visible light can be used. For example, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a silicon nitride oxide film, an aluminum oxide film, or the like can be used. The inorganic film can be either a single layer or a stacked layer.

Although the cover film 503 needs to reduce physical damage or the like of the display panel 501, it does not contribute to the suppression of moisture intrusion into the display panel. No problem. By using this microcrack, a cover film 503 having a high surface hardness and high bendability can be produced.

The cover film 503 may be subjected to a treatment having water repellency and oil repellency on the surface.

<< First casing, second casing >>
As the first housing and the second housing, a material capable of maintaining mechanical strength to some extent can be used. Specifically, plastic, metal, wood and the like can be used.

The second housing 504 is provided with a window in order to emit light from the display panel to the outside. A cover film is provided on the window.

The first housing 502 and the second housing 504 can be detached individually. If one of them breaks, it can be replaced with a new housing.

The cover film 503 and the second casing 504 that receive physical force from the outside are likely to be damaged before the display panel 501 and the first casing 502 and become unusable. In addition, since the first housing 502 and the second housing 504 can be removed, only the part to be replaced can be replaced, and repair can be made at low cost. Further, since the cover film 503 can be made cheaper than the display panel 501, it can be repaired cheaply by having a replacement function.

《Folding mechanism》
The folding mechanism 550 can be bent at the folding position of the first casing 502 and the second casing 504. For example, a hinge or a flexible member can be applied to the folding mechanism 550.

Note that a ratchet mechanism, a slipper, or the like may be provided in the folding mechanism 550 so that the bending angle can be adjusted as appropriate.

<Display panel>
The display panel 501 has flexibility.

A structure of the display panel 501 that can be applied to the display device 500 includes a display element that can display information included in a supplied signal. As a display element, a light emitting element, electronic ink, a liquid crystal element etc. are provided, for example. Note that a structure in which a light-emitting element is used as a display element as an example of the display panel 501 is described in detail in Embodiment 2.

Note that this embodiment can be combined with any of the other embodiments described in this specification as appropriate.

(Embodiment 2)
In this embodiment, a structure of a display panel applicable to the display device of one embodiment of the present invention will be described with reference to FIGS.

FIG. 4A is a top view illustrating a structure of a display panel applicable to the display device of one embodiment of the present invention.

FIG. 4B is a cross-sectional view taken along a cutting line AB and a cutting line CD in FIG.

FIG. 4C is a cross-sectional view taken along a cutting line EF in FIG.

<Explanation of top view>
The display panel 200 illustrated in this embodiment has one end 200L and the other end 200R (see FIG. 4A). Note that in one embodiment of the present invention, the display panel 200 may not include one or both of the one end 200L and the other end 200R.

In addition, the display panel 200 exemplified in this embodiment includes a display region 201.

The display area 201 is provided with a plurality of pixels 202, and the pixel 202 is provided with a plurality of subpixels (for example, a subpixel 202R). The sub-pixel is provided with a light-emitting element and a pixel circuit that can supply power for driving the light-emitting element.

The pixel circuit is electrically connected to a wiring that can supply a selection signal and a wiring that can supply a data signal.

The display panel 200 includes a scanning line driving circuit 203g that can supply a selection signal and a data line driving circuit 203s that can supply a data signal.

<Explanation of sectional view>
The display panel 200 includes a substrate 210 and a counter substrate 270 facing the substrate 210 (see FIG. 4B).

The substrate 210 is a stack of a flexible substrate 210b, a barrier film 210a that prevents diffusion into a light-emitting element, and an adhesive layer 210c that bonds the substrate 210b and the barrier film 210a together.

The counter substrate 270 is a stacked body of a flexible substrate 270b, a barrier film 270a that prevents diffusion into a light emitting element, and an adhesive layer 270c that bonds the substrate 270b and the barrier film 270a together.

Further, the sealing material 260 bonds the counter substrate 270 and the substrate 210 together. Further, the pixel circuit and the light-emitting element (eg, the first light-emitting element 250R) are between the substrate 210 and the counter substrate 270.

<Pixel configuration>
The pixel 202 includes a sub-pixel 202R, a sub-pixel 202G, and a sub-pixel 202B (see FIG. 4C). The subpixel 202R includes a light emitting module 280R, the subpixel 202G includes a light emitting module 280G, and the subpixel 202B includes a light emitting module 280B.

For example, the sub-pixel 202R includes a pixel circuit including a first light-emitting element 250R and a transistor 202t that can supply power to the first light-emitting element 250R (see FIG. 4B). The sub-pixel 202R includes a light emitting module 280R, and the light emitting module 280R includes a first light emitting element 250R and an optical element (for example, a first colored layer 267R).

The first light-emitting element 250R includes a first lower electrode 251R, an upper electrode 252, and a layer 253 containing a light-emitting organic compound between the first lower electrode 251R and the upper electrode 252.

The layer 253 containing a light-emitting organic compound includes a light-emitting unit 253a, a light-emitting unit 253b, and an intermediate layer 254 between the light-emitting unit 253a and the light-emitting unit 253b.

The light emitting module 280R includes the first colored layer 267R on the counter substrate 270. The colored layer may be any layer that transmits light having a specific wavelength. For example, a layer that selectively transmits light exhibiting red, green, blue, or the like can be used. Note that a region that directly transmits light emitted from the light-emitting element may be provided.

For example, the light-emitting module 280R includes the sealing material 260 in contact with the first light-emitting element 250R and the first colored layer 267R.

The first colored layer 267R overlaps with the first light emitting element 250R. Thus, part of the light emitted from the first light emitting element 250R passes through the sealing material 260 and the first colored layer 267R and is emitted to the outside of the light emitting module 280R as indicated by arrows in the drawing. .

<Display panel configuration>
The display panel 200 includes a light shielding layer 267BM on the counter substrate 270. The light shielding layer 267BM is provided so as to surround the colored layer (for example, the first colored layer 267R).

The display panel 200 includes an antireflection layer 267p at a position overlapping the display area 201.

The display panel 200 includes an insulating film 221. The insulating film 221 covers the transistor 202t. Note that the insulating film 221 can be used as a layer for planarizing unevenness caused by the pixel circuit. Further, an insulating film in which a layer capable of suppressing diffusion of impurities to the transistor 202t and the like is stacked can be used as the insulating film 221.

The display panel 200 includes a light-emitting element (eg, the first light-emitting element 250R) over the insulating film 221.

The display panel 200 includes a partition 228 which overlaps with the end portion of the first lower electrode 251R over the insulating film 221 (see FIG. 4C). In addition, a spacer 229 for controlling the distance between the substrate 210 and the counter substrate 270 is provided on the partition 228.

<Configuration of data line driving circuit>
The data line driver circuit 203s includes a transistor 203t and a capacitor 203c. Note that the driver circuit can be formed over the same substrate as the pixel circuit in the same process as the pixel circuit.

<Other configuration>
The display panel 200 includes a wiring 211 that can supply a signal, and a terminal 219 is provided in the wiring 211. Note that an FPC (flexible printed circuit) 209 that can supply signals such as a data signal and a synchronization signal is electrically connected to the terminal 219.

Note that a printed wiring board (PWB) may be attached to the FPC. The display panel in this specification includes not only the display panel body but also a state in which an FPC or PWB is attached thereto.

Note that this embodiment can be combined with any of the other embodiments described in this specification as appropriate.

200 Display Panel 200L Edge 200R Edge 201 Display Area 202 Pixel 202B Subpixel 202G Subpixel 202R Subpixel 202t Transistor 203c Capacitance 203g Scan Line Driver Circuit 203s Data Line Driver Circuit 203t Transistor 210 Substrate 210a Barrier Film 210b Substrate 210c Adhesive Layer 211 Wiring 219 Terminal 221 Insulating film 228 Partition 229 Spacer 250R Light emitting element 251R Lower electrode 252 Upper electrode 253 Layer 253a Light emitting unit 253b Light emitting unit 254 Intermediate layer 260 Sealing material 267BM Light shielding layer 267p Antireflection layer 267R Colored layer 270 Counter substrate 270a Barrier film 270b Substrate 270c Adhesive layer 280B Light emitting module 280G Light emitting module 280R Light emitting module 500 Display device 501 Display panel 502 First Housing 503 Cover film 504 Second housing 505 Display area 506 Visible light transmitting area 550 Folding mechanism

Claims (10)

A display device having a first housing, a display panel, and a first layer;
The first housing houses the display panel,
The display panel has flexibility,
The first layer has flexibility and transparency to visible light,
In a state where the display device is deployed, the first layer is located on the display surface of the display panel,
The first housing and the first layer can be folded independently of each other;
Said first housing, it has a plurality of folding portions,
In a state where the first housing is folded, one surface can be folded so that the display surface of the display panel is on the outside, and the other surface is folded on the back surface of the display panel.
The so as to cover one surface, Ru der possible to fold the said first layer, the display device. A display device having a first housing, a display panel, and a first layer;
The first housing houses the display panel,
The display panel has flexibility,
The first layer has flexibility and transparency to visible light,
In a state where the display device is deployed, the first layer is located on the display surface of the display panel,
The first housing and the first layer can be folded independently of each other;
It said first housing are three fold can der,
In a state where the first housing is folded, one surface can be folded so that the display surface of the display panel is on the outside, and the other surface is folded on the back surface of the display panel.
The so as to cover one surface, Ru der possible to fold the said first layer, the display device. In claim 1 or 2 ,
When folding, the first housing can be folded before the first layer, and then the first layer can be folded so as to cover the first housing. , Display device. In any one of Claims 1 thru | or 3 ,
The display device can be folded so that a part of the display surface of the display panel can be seen from the outside. In any one of Claims 1 thru | or 4 ,
Having a second housing;
The display device in which the second casing houses the first layer. In any one of Claims 1 thru | or 5 ,
A display device in which the first layer has a larger radius of curvature when folded. In any one of Claims 1 thru | or 6 ,
A display device having a touch sensor in the first layer. In any one of Claims 1 thru | or 7 ,
A display device comprising an antireflection layer on at least one of the surfaces of the first layer and the display panel facing each other. In any one of Claims 1 thru | or 8 ,
The display device, wherein the first casing and the first layer can be respectively removed. In any one of Claims 1 thru | or 9 ,
The display device, wherein the first layer is thicker than the display panel.

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