KR20230044738A - Stretchable display and display device having the same - Google Patents

Abstract

A disclosed stretchable display according to one embodiment comprises: a display panel equipped to enable a new construction, and equipped with normal pixels and compensation pixels; and an opening part equipped at an upper part of the display panel and corresponding to a position where the normal pixels are formed, and a potential opening part equipped in correspondence with a position where the compensation pixels are formed. Therefore, the present invention is capable of not requiring a separate driving method for driving the compensation pixels.

Description

Stretchable display and display device having the same {STRETCHABLE DISPLAY AND DISPLAY DEVICE HAVING THE SAME}

Embodiments of the present invention relate to stretchable display technology.

Display technology that brings changes to the form factor has been commercialized, going through a curved or bendable fixed flexible display in the first step, a rollable or foldable single-axis flexible display in the second step, and a third step A stretchable display is on the rise.

A stretchable display is a next-generation display in which the screen is elastically stretched. According to future research results, a wearable device attached to the body or clothes, a head-up display inserted into the windshield of a vehicle that expands or contracts minutely depending on external temperature, In addition, it is expected to be applied to various products such as display devices that require adjustment of the display screen.

One of the technical challenges of the stretchable display is that the pixel resolution of the stretchable display is changed before and after stretching. When the stretchable display is stretched, the number of pixels per unit area decreases, resulting in a change in resolution. When the resolution changes due to the tension of the display, the image displayed on the display may be distorted.

In order to solve this problem, a compensation pixel was introduced in addition to the normal pixel, but a driving method separate from the normal pixel is required when driving the compensation pixel, which can complicate the manufacturing process of the stretchable display. There is a problem of decreasing. Therefore, there is a need for a method capable of maintaining resolution and luminance without requiring a separate driving method while introducing a compensation pixel.

Korean Patent Publication No. 10-2017-0100719 (2017.09.05)

According to one aspect of the disclosed invention, it is possible to provide a stretchable display capable of maintaining resolution and luminance when stretched, and a display device including the same.

On the other hand, the technical problems to be achieved in the present invention are not limited to the above-mentioned technical problems, and other technical problems that are not mentioned will become clear to those skilled in the art from the description below. You will be able to understand.

A stretchable display according to an aspect of the disclosed subject matter includes a display panel that is stretchable and has normal pixels and compensation pixels provided thereon; and an opening provided above the display panel to correspond to a position where the normal pixels are formed, and a latent opening provided to correspond to a position where the compensation pixels are formed.

The compensation pixel is a pixel for compensating for luminance and resolution of the stretchable display when the stretchable display is stretched, the opening is provided in an open state to expose the normal pixel, and the latent opening is , Light emitted from the compensation pixel may be displayed externally according to the tension of the stretchable display.

The latent opening may be provided such that an open degree thereof varies according to a degree of tension of the stretchable display.

The latent opening may not be opened before the stretchable display is stretched, but the open area may increase according to the degree to which the stretchable display is stretched.

The latent opening may include a first cutting pattern having one or more cutting lines crossing an area of the latent opening in a predetermined direction.

The first cutting pattern may include a first cutting line provided to cross the center of the latent opening in a first direction; and a second cutting line provided to cross the center of the latent opening in a second direction different from the first direction.

The latent opening may further include a second cutting pattern having a partial incision line provided along an edge of the latent opening.

The display panel may include a stretchable substrate; a rigid region provided on the stretchable substrate and in which the normal pixels and the compensation pixels are formed; and an elongation region provided on the stretchable substrate and provided in a region other than the rigid region, wherein the panel cover may have a Young's modulus greater than that of the stretchable substrate and the elongation region.

The display panel may include a stretchable substrate; a rigid region provided on the stretchable substrate and in which the normal pixels and the compensation pixels are formed; and an elongation region provided on the upper portion of the stretchable substrate and provided in addition to the rigid region, wherein the elongation region may be formed by stacking a plurality of layers having different Young's moduli.

The plurality of layers may have a Young's modulus greater as they are closer to the stretchable substrate and a Young's modulus smaller as they are closer to the panel cover.

Transparency of the latent opening may vary as the stretchable display is stretched.

Transparency of the latent opening may increase as the stretchable display is stretched.

In a stretchable display according to an aspect of the present disclosure, an opening is formed in an area corresponding to a normal pixel on a panel cover and a latent opening is formed in an area corresponding to a compensation pixel, and compensation pixels as well as normal pixels are always turned on. By maintaining the present state, resolution and luminance can be maintained even when the stretchable display is stretched, and a separate driving method for driving the compensation pixel is not required.

On the other hand, the effects obtainable in the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

1 is a diagram schematically illustrating a stretchable display according to an exemplary embodiment of the present invention.
2 is a diagram illustrating a tensile state according to a pixel arrangement structure in a stretchable display according to an embodiment of the present invention.
3 is a diagram illustrating a tensile state according to a pixel arrangement structure in a stretchable display according to another embodiment of the present invention.
4 is a cross-sectional view of a stretchable display according to a first embodiment of the present invention.
5 is a cross-sectional view of a stretchable display according to a second embodiment of the present invention.
6 is a cross-sectional view of a stretchable display according to a third embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. Embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited to the following examples. This embodiment is provided to more completely explain the present invention to those skilled in the art. Accordingly, the shapes of elements in the figures are exaggerated to emphasize clearer description.

The composition of the present invention for clarifying the solution to the problem to be solved by the present invention will be described in detail with reference to the accompanying drawings based on a preferred embodiment of the present invention, but the same reference numerals are assigned to the components of the drawings. For components, even if they are on other drawings, the same reference numerals have been given, and it is made clear in advance that components of other drawings can be cited if necessary in the description of the drawings.

Meanwhile, directional terms such as upper side, lower side, one side, and the other side are used in relation to the orientation of the disclosed drawings. Since components of embodiments of the present invention may be positioned in a variety of orientations, directional terms are used for purposes of illustration and not limitation.

Also, terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms may be used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present invention.

1 is a diagram schematically illustrating a stretchable display according to an exemplary embodiment of the present invention.

Referring to FIG. 1 , a stretchable display 100 may include a display panel 102 and a panel cover 104 .

The stretchable display 100 may be a display capable of displaying an image even when bent or stretched.

The stretchable display 100 may have high flexibility compared to conventional general displays. That is, the shape of the stretchable display 100 can be freely changed according to a user's manipulation, such as when the user bends or stretches the stretchable display 100 .

For example, when a user grabs an end of the stretchable display 100 and pulls it, the stretchable display 100 may be stretched by the user's force. Alternatively, when a user places the stretchable display 100 on a wall that is not flat, the stretchable display 100 may be bent along the shape of the surface of the wall. Also, when the force applied by the user is removed, the stretchable display 100 may return to its original shape.

The display panel 102 may be provided to be stretchable in one or more directions of the first direction and the second direction. That is, the display panel 102 may be provided to be stretchable in a first direction (eg, an x-axis direction) or a second direction (eg, a y-axis direction).

In addition, the display panel 102 may be provided to be stretchable simultaneously in the first direction and the second direction. Here, the first direction and the second direction form a plane of the stretchable display 100, and the second direction may be perpendicular to the first direction.

The display panel 102 may include normal pixels 111 and compensation pixels 113 .

The normal pixel 111 may be a pixel displayed even before the stretchable display 100 is stretched.

The compensation pixel 113 may be a pixel that is not displayed before the stretchable display 100 is stretched, but is displayed when the stretchable display 100 is stretched.

That is, the compensation pixel 113 may be a pixel for compensating the luminance and resolution of the stretchable display 100 when the stretchable display 100 is stretched.

The normal pixel 111 and the compensation pixel 113 may each include a light emitting element and a driving circuit for driving the light emitting element. The normal pixel 111 and the compensation pixel 113 may emit light of any one color among red, green, and blue according to the light color of each light emitting device.

Here, the light emitting device is a light emitting device such as an organic light emitting diode (OLED), a polymer light emitting diode (PLED), a quantum dot (QD), or a light emitting diode (LED). It may be, but is not limited thereto. The light emitting elements of the normal pixels 111 and the compensation pixels 113 and driving circuits for driving them are well-known technologies, so detailed descriptions thereof will be omitted.

Meanwhile, the normal pixels 111 and the compensation pixels 113 may always remain turned on while the stretchable display 100 is driven. That is, in the disclosed embodiment, the compensation pixel 113 may maintain an on state not only while the stretchable display 100 is stretched but also before being stretched and thus not displayed.

A panel cover 104 may be disposed on top of the display panel 102 .

The panel cover 104 may be provided by being bonded to the display panel 102 at an upper portion of the display panel 102 .

The panel cover 104 may be made of a flexible or stretchable material. That is, the panel cover 104 may be made of a material having elasticity. For example, the panel cover 104 may be made of an elastic polymer such as polydimethysiloxane (PDMS), silicone rubber, polyurethane, etc., but is not limited thereto.

In an exemplary embodiment, the panel cover 104 may be made of a material having a different Young's modulus from that of the display panel 102, but is not limited thereto, and the Young's modulus of the panel cover 104 and the display panel ( 102) may have the same Young's modulus.

The Young's modulus is an elastic modulus representing the rate of deformation by the stress applied to the material, and a material having a relatively high Young's modulus may have relatively higher strength than other materials.

The panel cover 104 may include an opening 121 and a latent opening 123 . The opening 121 may be provided at a position corresponding to the normal pixel 111 .

The opening 121 may be provided in an open state with a size corresponding to that of the normal pixel 111 . That is, the opening 121 may be always open by removing a portion of the panel cover 104 (corresponding to the normal pixel 111) after being cut.

As the opening 121 is always provided in an open state, the normal pixels 111 positioned below the opening 121 are exposed by the opening 121, and light from the normal pixels 111 It can be emitted and displayed.

The latent opening 123 may be provided at a position corresponding to the compensation pixel 113 .

Unlike the opening 121 , the latent opening 123 does not always remain open, but may be prepared to have a different degree of opening depending on the degree of tension of the stretchable display 100 .

The latent opening 123 does not open before the stretchable display 100 is stretched, but starts to open as the stretchable display 100 is stretched, and the degree of stretching of the stretchable display 100 increases. An open area may be provided to increase accordingly.

To this end, a first cutting pattern 123a and a second cutting pattern 123b may be provided in the latent opening 123 .

The first cutting pattern 123a may include one or more cutting lines crossing the area of the latent opening 123 in a certain direction. In an exemplary embodiment, the first cutting pattern 123a may include a first cutting line 123a-1 and a second cutting line 123a-2.

The first cutting line 123a-1 may be provided to cross the center of the latent opening 123 in the first direction.

The second cutting line 123a-2 may be provided while crossing the center of the latent opening 123 in a second direction different from the first direction.

Here, the second cutting line 123a-2 may perpendicularly cross the first cutting line 123a-1, but is not limited thereto.

The second cutting pattern 123b may be provided along an edge of the latent opening 123 (ie, a region corresponding to the compensation pixel 113).

The second cutting pattern 123b may be formed of partial cutting lines. In this case, the partial incision line may be formed of a dotted line, a one-dot chain line, a two-dot chain line, or the like.

In this way, by providing the first cutting pattern 123a and the second cutting pattern 123b in the latent opening 123, the latent opening 123 is not opened until the stretchable display 100 is stretched, resulting in compensation pixels ( 113) is in a covered state, and as the stretchable display 100 is stretched, the potential opening 123 starts to open, and the open area increases as the degree of stretching of the stretchable display 100 increases. Thus, the compensation pixel 113 is in an exposed state.

Meanwhile, although the first cutting pattern 123a has been described as including the first cutting line 123a-1 and the second cutting line 123a-2, it is not limited thereto and the first cutting line 123a-1 ) and the second cutting line 123a-2.

Also, the latent opening 123 may include only the first cutting pattern 123a without the second cutting pattern 123b.

According to the disclosed embodiment, an opening 121 is formed in an area corresponding to the normal pixel 111 in the panel cover 104, and a latent opening 123 is formed in an area corresponding to the compensation pixel 113, By keeping the compensation pixels 113 as well as the normal pixels 111 always turned on, the resolution and luminance can be maintained even when the stretchable display 100 is stretched. drive method is not required.

2 is a diagram showing a tensile state according to a pixel arrangement structure in a stretchable display according to an embodiment of the present invention, and FIG. 3 is a view showing a stretchable state according to a pixel arrangement structure in a stretchable display according to another embodiment It is a drawing showing the tension state.

Referring to FIG. 2 , R, G, and B normal pixels 111 are arranged at regular intervals on the display panel 102, and the compensation pixels 113 are different from the normal pixels 111 in columns and rows. It can be seen that the pixel 111 is arranged in a diagonal direction. Also, a case in which the first cutting pattern 123a of the latent opening 123 includes the first cutting line 123a-1 and the second cutting line 123a-2 is shown.

Referring to FIG. 3 , it can be seen that the compensation pixels 113 are arranged in positions corresponding to the normal pixels 111 while having different columns and rows from the normal pixels 111 . Also, a case in which the first cutting pattern 123a of the latent opening 123 includes the first cutting line 123a-1 or the second cutting line 123a-2 is shown.

Meanwhile, the illustrated arrangement of the normal pixels 111 and compensation pixels 113 is only an example, and various arrangements may be provided.

Here, since the normal pixels 111 are exposed by the opening 121 even before the stretchable display 100 is stretched, colors are displayed to the outside.

On the other hand, since the latent openings 123 of the compensation pixels 113 are closed before the stretchable display 100 is stretched, colors are not displayed outside even when the compensation pixels 113 are turned on.

The stretchable display 100 moves in any one of a first direction (x-axis direction), a second direction (y-axis direction), and a first direction (x-axis direction) and a second direction (y-axis direction). When the tension starts, the latent opening 123 is opened, and the compensation pixel 113 positioned below the latent opening 123 is exposed to display a color.

4 is a cross-sectional view of a stretchable display according to a first embodiment of the present invention.

Referring to FIG. 4 , the display panel 102 includes a stretchable substrate 131 . The stretchable substrate 131 may be made of a stretchable insulating material.

A rigid region 133 and an elongated region 135 may be formed on the stretchable substrate 131 . Normal pixels 111 and compensation pixels 113 may be formed on top of the rigid region 133 .

A layer structure and component elements constituting driving circuits of the normal pixels 111 and the compensation pixels 113 may be formed in the rigid region 133 .

The stretching region 135 may be provided in a space between the pixels 111 and 113 on the stretchable substrate 131 .

The stretched region 135 may be stretched according to an external pulling force. For example, the stretched region 135 may be made of the same material as the stretchable substrate 131 .

A panel cover 104 may be provided on top of the display panel 102 by being bonded thereto.

The opening 121 of the panel cover 104 may be provided at a position corresponding to the normal pixel 111 to expose the normal pixel 111 to the outside.

The latent opening 123 of the panel cover 104 may be provided at a position corresponding to the compensation pixel 113 to cover the compensation pixel 113 .

Here, the Young's modulus Y2 of the panel cover 104 may be greater than the Young's modulus Y1 of the stretchable substrate 131 and the stretching region 135 . In this case, when the stretchable display 100 is stretched, the panel cover 104 is less stretched than the stretchable substrate 131 and the stretching area 135, and as a result, the latent opening 123 is opened, and the compensation pixel (113) is exposed to the outside.

That is, since the Young's modulus (Y2) of the panel cover 104 is greater than the Young's modulus (Y1) of the stretchable substrate 131 and the stretching region 135, when the stretchable display 100 is stretched, the panel cover A difference occurs in the degree of tension between the stretchable substrate 131 and the stretchable region 135 and the resulting physical force causes the latent opening 123 to open.

5 is a cross-sectional view of a stretchable display according to a second embodiment of the present invention.

Referring to FIG. 5 , in the display panel 102 , the stretching region 135 may include a plurality of layers having different Young's moduli.

For example, the stretched region 135 may be formed by sequentially stacking a first stretched layer 135-1, a second stretched layer 135-2, and a third stretched layer 135-3. . In this case, the first stretched layer 135 - 1 may be formed on the upper surface of the stretchable substrate 131 .

Here, the Young's modulus (Y3) of the first stretched layer 135-1 is the largest, the Young's modulus (Y2) of the second stretched layer 135-2 is next largest, and the Young's modulus (Y2) of the third stretched layer 135-3 is the largest. The Young's modulus (Y1) may be provided to be the smallest.

That is, the stacked stretched layers may have a Young's modulus greater as they are closer to the stretchable substrate 131 and a Young's modulus smaller as they are closer to the panel cover 104 .

For example, the first elongated layer 135-1 is made of styrene-butadiene rubber (Young's modulus: 6), the second elongated layer 135-2 is made of nitrile rubber (Young's modulus: 4), and the third The stretched layer 135-3 may be made of PDMS (Young's modulus: 0.57), but is not limited thereto.

In this case, when the stretchable display 100 is stretched, the first stretchable layer 135-1 → the second stretchable layer 135-2 → the third stretchable layer 135-3 is more stretched in the order. , the latent opening 123 is opened by the resulting physical force, and the compensation pixel 113 is exposed to the outside.

In this case, the Young's modulus of the panel cover 104 may be greater than the Young's modulus (Y1) of the third stretched layer 135-3. For example, the Young's modulus of the panel cover 104 may be the same as the Young's modulus (Y2) of the second stretched layer 135-2 or the Young's modulus (Y3) of the first stretched layer 135-1. It is not limited.

6 is a cross-sectional view of a stretchable display according to a third embodiment of the present invention.

Referring to FIG. 6 , the latent opening 123 may have a different transparency as the stretchable display 100 is stretched.

For example, the latent opening 123 may be prepared to be in an opaque state before the stretchable display 100 is stretched, and change to a transparent state when the stretchable display 100 is stretched.

That is, the transparency of the latent opening 123 changes even though it is not physically opened as the stretchable display 100 is stretched, so that the compensation pixels 113 corresponding to the latent opening 123 are not well visible before stretching. may be arranged to be visible after tensioning.

In an exemplary embodiment, the latent opening 123 may have transparency that increases as the stretchable display 100 is stretched.

To this end, the surface of the region where the latent opening 123 is formed may be formed with a wave pattern (or a wrinkle pattern). The wave pattern may have a width of a micro unit or a nano unit. And, a metal thin film may be coated on the surface of the wavy pattern. At this time, the metal thin film may be formed to a thickness of 10 to 20 nm, but is not limited thereto.

In this case, the latent opening 123 is in an opaque state before the stretchable display 100 is stretched, and changes to a transparent state when the stretchable display 100 is stretched. That is, before the stretchable display 100 is stretched, light does not pass through well due to the wrinkle pattern, but when the stretchable display 100 is stretched, the wrinkle pattern is stretched, so light can pass through.

Meanwhile, the method for changing the transparency of the latent opening 123 does not necessarily have to be the method by the above-described wave pattern, and if the transparency of the opening 123 can be changed according to the degree of tension of the stretchable display 100, any method It doesn't matter if you follow

The above detailed description is illustrative of the present invention. In addition, the foregoing is intended to illustrate and describe preferred embodiments of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, changes or modifications are possible within the scope of the concept of the invention disclosed in this specification, within the scope equivalent to the written disclosure and / or within the scope of skill or knowledge in the art. The written embodiment describes the best state for implementing the technical idea of the present invention, and various changes required in the specific application field and use of the present invention are also possible. Therefore, the above detailed description of the invention is not intended to limit the invention to the disclosed embodiments. Also, the appended claims should be construed to cover other embodiments as well.

100: stretchable display
102: display panel
104: panel cover
111: normal pixel
113: compensation pixel
121: opening
123 Latent opening
123a: first cutting pattern
123a-1: first incision
123a-2: second incision
123b: second cutting pattern
131: stretchable substrate
133 stiffness region
135 stretching area
135-1: first stretched layer
135-2: second stretch layer
135-3: third stretch layer

Claims (13)

a display panel provided to be stretchable and provided with normal pixels and compensation pixels; and
A stretchable display comprising an opening provided above the display panel to correspond to a position where the normal pixels are formed, and a latent opening provided to correspond to a position where the compensation pixels are formed. The method of claim 1,
The compensation pixel is a pixel for compensating for luminance and resolution of the stretchable display when the stretchable display is stretched;
The opening is provided in an open state to expose the normal pixel,
The stretchable display of claim 1 , wherein the latent opening is provided so that light emitted from the compensation pixel is displayed outside according to the tension of the stretchable display. The method of claim 2,
The potential opening,
A stretchable display provided so that an open degree varies according to a degree of tension of the stretchable display. The method of claim 3,
The potential opening,
Wherein the stretchable display is not opened before the stretchable display is stretched, but the open area increases according to the extent to which the stretchable display is stretched. The method of claim 2,
The potential opening,
A stretchable display comprising a first cutting pattern having one or more cutting lines crossing an area of the latent opening in a predetermined direction. The method of claim 5,
The first cutting pattern,
a first cutting line provided to cross the center of the latent opening in a first direction; and
A stretchable display comprising: a second cutting line provided to cross the center of the latent opening in a second direction different from the first direction. The method of claim 5,
The potential opening,
The stretchable display further includes a second cutting pattern having a partial cutting line provided along an edge of the latent opening. The method of claim 5,
The display panel,
a panel cover including the opening and the latent opening;
stretchable substrate;
a rigid region provided on the stretchable substrate and in which the normal pixels and the compensation pixels are formed; and
A stretching region provided on the upper portion of the stretchable substrate and provided in addition to the rigid region;
The stretchable display of claim 1 , wherein a Young's modulus of the panel cover is greater than Young's modulus of the stretchable substrate and the stretchable region. The method of claim 5,
The display panel,
a panel cover including the opening and the latent opening;
stretchable substrate;
a rigid region provided on the stretchable substrate and in which the normal pixels and the compensation pixels are formed; and
A stretching region provided on the upper portion of the stretchable substrate and provided in addition to the rigid region;
The stretchable display is formed by stacking a plurality of layers having different Young's moduli. The method of claim 9,
The plurality of layers,
The stretchable display is provided so that the Young's modulus increases as it is closer to the stretchable substrate and the Young's modulus decreases as it is closer to the panel cover. The method of claim 2,
The potential opening,
The stretchable display provided to have a different transparency as the stretchable display is stretched. The method of claim 11,
The potential opening,
A stretchable display provided so that transparency increases as the stretchable display is stretched. A display device comprising the stretchable display according to any one of claims 1 to 12.

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