Patent Application
20250012946
The present inventive concept relates to a display device, and more particularly, to a display device including an anti-reflection layer.
In the related art, a polarization film is attached on a display surface of a display device so as to prevent the reflection of external light.
Because the polarization film includes a linear polarization film and a ¼% phase retardation film, a thickness of the polarization film is considerable.
Therefore, in a display device of the related art, there is a drawback where a thickness thereof is thick due to the polarization film, and due to the thick thickness, there is a limitation in implementing a rollable or foldable display device. Also, in a case where the polarization film is applied to the rollable or foldable display device, there is a problem where the polarization film having a thick thickness is stripped when an operation of rolling or bending the display device is repeated.
The present inventive concept is devised to solve the above-described problem and is for providing a display device in which an anti-reflection layer having a thin thickness is included therein, and thus, it is easy to implement a rollable or foldable display device and a problem where the anti-reflection layer is stripped may be prevented.
To accomplish the above-described objects, the present inventive concept provides a display device including: a first electrode provided on a substrate; a light emitting layer provided on the first electrode; a second electrode provided on the light emitting layer; and an anti-reflection layer provided on the second electrode, the anti-reflection layer including a light-absorbing material, wherein the light-absorbing material includes at least one material selected from the group consisting of amorphous carbon (a-C), a polymer, a monomer, metal, metal oxide, and graphite.
The metal may include at least one material selected from the group consisting of tungsten and molybdenum.
The tungsten may include at least one material selected from the group consisting of [Bis(tert-butylimino)bis (dimethylamino)tungsten(VI)], [Pentacarbonyl(N,N-dimethylmethanamine)tungsten], and [pentacarbonyl(1-methylpyrrolidine)tungsten].
A first interface layer may be additionally provided on a top surface of the anti-reflection layer, and the first interface layer may have a refractive index between a refractive index of the anti-reflection layer and a refractive index of a layer, contacting the first interface layer, on the first interface layer.
The first interface layer may include at least one material selected from the group consisting of silicon nitride and silicon oxide.
A second interface layer may be additionally provided on a bottom surface of the anti-reflection layer, and the second interface layer may have a refractive index between a refractive index of the anti-reflection layer and a refractive index of a layer, contacting the second interface layer, under the second interface layer.
The second interface layer may include at least one material selected from the group consisting of silicone nitride and silicone oxide.
An encapsulation layer may be additionally provided on the second electrode, and the anti-reflection layer may be provided between the second electrode and the encapsulation layer.
An encapsulation layer including a first encapsulation layer and a second encapsulation layer may be additionally provided on the second electrode, and the anti-reflection layer may be provided between the first encapsulation layer and the second encapsulation layer.
An encapsulation layer and a hard coating layer may be additionally provided on the second electrode, and the anti-reflection layer may be provided between the encapsulation layer and the hard coating layer.
A hard coating layer may be additionally provided on the second electrode, and the anti-reflection layer may be provided on a top surface of the hard coating layer.
Moreover, the present inventive concept provides a display device including: a first electrode provided on a substrate; a light emitting layer provided on the first electrode; a second electrode provided on the light emitting layer; and an anti-reflection layer provided under the second electrode, the anti-reflection layer including a light-absorbing material, wherein the light-absorbing material includes at least one material selected from the group consisting of amorphous carbon (a-C), a polymer, a monomer, metal, and graphite.
The metal may include at least one material selected from the group consisting of tungsten and molybdenum.
The tungsten may include at least one material selected from the group consisting of [Bis(tert-butylimino)bis (dimethylamino)tungsten(VI)], [Pentacarbonyl(N,N-dimethylmethanamine)tungsten], and [pentacarbonyl(1-methylpyrrolidine)tungsten].
A first interface layer may be additionally provided on a bottom surface of the anti-reflection layer, and the first interface layer may have a refractive index between a refractive index of the anti-reflection layer and a refractive index of a layer, contacting the first interface layer, under the first interface layer.
The first interface layer may include at least one material selected from the group consisting of silicone nitride and silicone oxide.
A second interface layer may be additionally provided on a top surface of the anti-reflection layer, and the second interface layer may have a refractive index between a refractive index of the anti-reflection layer and a refractive index of a layer, contacting the second interface layer, on the second interface layer.
The second interface layer may include at least one material selected from the group consisting of silicone nitride and silicone oxide.
A circuit element layer may be additionally provided on the substrate, and the anti-reflection layer may be provided between the substrate and the circuit element layer.
The anti-reflection layer may be provided on a bottom surface of the substrate.
According to an embodiment of the present inventive concept, because a light-absorbing material layer which is formed to have a thin thickness through a chemical vapor deposition process and includes at least one material selected from the group consisting of amorphous carbon (a-C), a polymer, a monomer, metal, metal oxide, and graphite is used as an anti-reflection layer, it is easy to implement a rollable or foldable display device as a thickness of the anti-reflection layer is thin, and moreover, a problem where the anti-reflection layer is stripped may be prevented even when the rollable or foldable display device is repeatedly rolled or bent.
Moreover, according to an embodiment of the present inventive concept, a light absorption rate of the anti-reflection layer may be adjusted by adjusting a thickness of the light-absorbing material layer, and thus, a reflectance of external light may be adjusted, thereby implementing a thin thickness and obtaining an effect which is similar to or better than that of an anti-reflection layer including a polarization film of the related art.
Advantages and features of the present inventive concept, and implementation methods thereof will be clarified through following embodiments described with reference to the accompanying drawings. The present inventive concept may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this inventive concept will be thorough and complete, and will fully convey the scope of the present inventive concept to those skilled in the art. Furthermore, the present inventive concept is only defined by scopes of claims.
A shape, a size, a ratio, an angle, and a number disclosed in the drawings for describing embodiments of the present inventive concept are merely an example, and thus, the present inventive concept is not limited to the illustrated details. Like reference numerals refer to like elements throughout. In the following description, when the detailed description of the relevant known technology is determined to unnecessarily obscure the important point of the present inventive concept, the detailed description will be omitted. In a case where ‘comprise’, ‘have’, and ‘include’ described in the present specification are used, another part may be added unless ‘only˜’ is used. The terms of a singular form may include plural forms unless referred to the contrary.
In construing an element, the element is construed as including an error range although there is no explicit description.
In describing a position relationship, for example, when a position relation between two parts is described as ‘on˜’, ‘over˜’, ‘under˜’, and ‘next˜’, one or more other parts may be disposed between the two parts unless ‘just’ or ‘direct’ is used.
In describing a time relationship, for example, when the temporal order is described as ‘after˜’, ‘subsequent˜’, ‘next˜’, and ‘before˜’, a case which is not continuous may be included unless ‘just’ or ‘direct’ is used.
It will be understood that, although the terms “first”, “second”, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the present inventive concept.
Features of various embodiments of the present inventive concept may be partially or overall coupled to or combined with each other, and may be variously inter-operated with each other and driven technically as those skilled in the art can sufficiently understand. The embodiments of the present inventive concept may be carried out independently from each other, or may be carried out together in co-dependent relationship.
Hereinafter, preferable embodiments of the present inventive concept will be described in detail with reference to the accompanying drawings.
As seen in
The display device according to an embodiment of the present inventive concept may be implemented as a top emission type where emitted light is upward discharged, and thus, the substrate 100 may include a transparent material such as glass as well as an opaque material such as plastic.
In a case where plastic is used as a material of the substrate 100, considering that a high temperature deposition process is performed on the substrate 100, polyimide which is capable of enduring a high temperature and is good in heat-resistant properties may be used as a material of the substrate 100, but the present embodiment is not limited thereto.
The circuit element layer 200 is formed on the substrate 100.
The circuit element layer 200 may include a gate electrode 210, a gate insulation layer 220, an active layer 230, a source electrode 240, a drain electrode 250, and a passivation layer 260. Although not shown, a buffer layer may be additionally formed between the substrate 100 and the gate electrode 210.
The gate electrode 210 is patterned on the substrate 100, and the gate insulation layer 220 is formed between the gate electrode 210 and the active layer 230 to insulate the gate electrode 210 from the active layer 230. The gate insulation layer 220 may include an inorganic insulating material such as silicone oxide or silicone nitride.
The active layer 230 is formed on the gate electrode 210 to overlap the gate electrode 210. The active layer 230 may include various semiconductor materials, such as a silicone-based semiconductor material or an oxide semiconductor material, known to those skilled in the art.
The source electrode 240 extends toward one side of the active layer 230 on the active layer 230, and the drain electrode 250 faces the source electrode 240 and extends toward the other side of the active layer 230 on the active layer 230.
A driving thin film transistor is configured by a combination of the gate electrode 210, the gate insulation layer 220, the active layer 230, the source electrode 240, and the drain electrode 250. The driving thin film transistor, as illustrated, may be formed in a bottom gate structure where the gate electrode 210 is provided under the active layer 230, but is not limited thereto and may also be formed in a top gate structure where the gate electrode 210 is provided on the active layer 230.
The passivation layer 260 is provided on the source electrode 240 and the drain electrode 250 to protect the driving thin film transistor. The passivation layer 260 may include an inorganic insulating material such as silicone oxide or silicone nitride. Although not shown, a planarization layer including an organic insulating material may be additionally formed between the passivation layer 260 and the first electrode 300.
The first electrode 300 is formed on the passivation layer 260. The first electrode 300 may be connected to the drain electrode 250 through a contact hole provided in the passivation layer 260. The first electrode 300 may function as an anode of the display device. The first electrode 300 may include a reflection layer so that light emitted from the light emitting layer 500 travels upward.
The bank 400 is formed on the passivation layer 260 to cover both ends of the first electrode 300. An exposure region of the first electrode 300, which is not covered and is exposed by the bank 400, may be an emission area. That is, the emission area may be defined by the bank 400. The bank 400 may be formed in a boundary region between a plurality of pixels, and thus, may be wholly formed in a matrix structure.
The light emitting layer 500 may be patterned on the first electrode 300. Particularly, the light emitting layer 500 may be formed in the emission area defined by the bank 400, and depending on the case, may extend up to a portion of a top surface of the bank 400. The light emitting layer 500 may include a red light emitting layer, a green light emitting layer, or a blue light emitting layer, which is patterned for each pixel.
The light emitting layer 500 may include a white light emitting layer, and in this case, the light emitting layer 500 may be formed in a stack structure where a red light emitting layer, a green light emitting layer, and a blue light emitting layer are stacked, or may be formed in a stack structure where a yellowish green light emitting layer and a blue light emitting layer are stacked. When the light emitting layer 500 includes the white light emitting layer, the light emitting layer 500 may be formed in a structure where the light emitting layer is not patterned for each of the plurality of pixels and is continued between the plurality of pixels.
The second electrode 600 is formed on the light emitting layer 500. The second electrode 600 may function as a common electrode in the plurality of pixels, and thus, may be continuously formed between the plurality of pixels without being disconnected. The second electrode 600 may function as a cathode of the display device. The display device according to an embodiment of the present inventive concept may be implemented as the top emission type, and thus, the second electrode 600 may include a transparent electrode or a semitransparent electrode.
The anti-reflection layer 700 is formed on the second electrode 600. In detail, the anti-reflection layer 700 is formed between the second electrode 600 and the encapsulation layer 800.
The anti-reflection layer 700 includes a material for absorbing light, and particularly, includes amorphous carbon (a-C). The amorphous carbon (a-C) may be deposited on the second electrode 600 through a chemical vapor deposition (CVD) process.
When the anti-reflection layer 700 includes the amorphous carbon (a-C), a film thickness of the amorphous carbon (a-C) may be adjusted, and thus, a light absorption rate of the anti-reflection layer 700 may be adjusted, thereby adjusting a reflectance of external light.
For example, in a case where the anti-reflection layer 700 is configured to absorb 50% light by adjusting the film thickness of the amorphous carbon (a-C), in a process where external light is incident on the inside of the display device, the anti-reflection layer 700 absorbs 50% light and only 50% light is transmitted to the inside of the display device, and when the transmitted light is reflected by an internal electrode or line of the display device, the anti-reflection layer 700 may again absorb 50% light, thereby allowing only 25% external light to be reflected finally.
Moreover, in displaying an image, only 50% of light emitted from the light emitting layer 500 may be absorbed by the anti-reflection layer 700, and an image may be displayed while discharging 50% light to the outside. As a result, 50% light may be discharged to the outside in displaying an image, but only 25% external light may be reflected in reflecting external light, thereby obtaining an effect which is similar to or better than that of an anti-reflection layer including a polarization film of the related art.
As described above, according to an embodiment of the present inventive concept, because the amorphous carbon (a-C) formed to have a thin thickness through a chemical vapor deposition process is used as the anti-reflection layer 700, it is easy to implement a rollable or foldable display device as a thickness of the anti-reflection layer 700 is thin, and moreover, a problem where the anti-reflection layer 700 is stripped may be prevented even when the rollable or foldable display device is repeatedly rolled or bent.
In addition to the amorphous carbon (a-C), a polymer, a monomer, metal, metal oxide, and graphite for absorbing light may be used as a material of the anti-reflection layer 700.
Accordingly, the anti-reflection layer 700 may include at least one material selected from the group consisting of amorphous carbon (a-C), a polymer, a monomer, metal, metal oxide, and graphite.
The polymer may be implemented at the low cost through a coating process of a printing process with atmospheric pressure.
The monomer has an advantage where it is possible to perform an evaporation process without vacuum break in a vacuum state.
The metal may include at least one material selected from the group consisting of tungsten and molybdenum. In this case, the tungsten may include at least one material selected from the group consisting of [Bis(tert-butylimino)bis (dimethylamino)tungsten(VI)], [Pentacarbonyl(N,N-dimethylmethanamine)tungsten], and [pentacarbonyl(1-methylpyrrolidine)tungsten].
The encapsulation layer 800 is formed on the anti-reflection layer 700. The encapsulation layer 800 may prevent external water from penetrating into the light emitting layer 500. The encapsulation layer 800 may include an inorganic insulating material, or may be formed in a structure where an inorganic insulating material and an organic insulating material are alternately stacked, but is not limited thereto.
The hard coating layer 900 is formed on the encapsulation layer 800. The hard coating layer 900 may be a layer which prevents a scratch of a surface of the display device and may perform a function of increasing the mechanical strength of the surface of the display device. The hard coating layer 900 may include various transparent materials known to those skilled in the art.
As seen in
The first interface layer 710 allows external light passing through the encapsulation layer 800 to travel to an inner portion of the anti-reflection layer 700 without being totally reflected from the top surface of the anti-reflection layer 700. The first interface layer 710 is provided to have a refractive index within a range between a refractive index of the anti-reflection layer 700 and a refractive index of the encapsulation layer 800.
When a refractive index difference between a refractive index of the anti-reflection layer 700 and a refractive index of the encapsulation layer 800 is large, a problem occurs where external light incident through the encapsulation layer 800 does not travel to the inner portion of the anti-reflection layer 700 and is totally reflected from the top surface of the anti-reflection layer 700, and thus, in another embodiment of the present inventive concept, because the first interface layer 710 is additionally formed between the anti-reflection layer 700 and the encapsulation layer 800, the refractive index difference between a refractive index of the anti-reflection layer 700 and a refractive index of the encapsulation layer 800 is compensated for, thereby enabling external light to easily travel the inner portion of the anti-reflection layer 700.
The first interface layer 710 may include metal oxide such as silicone oxide, tungsten oxide, or titanium oxide, or may include silicone nitride.
As seen in
The second interface layer 720 allows external light reflected from the inside of a display device to travel toward the anti-reflection layer 700 and travel to an inner portion of the anti-reflection layer 700 without staying in the display device. The second interface layer 720 is provided to have a refractive index within a range between a refractive index of the anti-reflection layer 700 and a refractive index of the second electrode 600.
When a refractive index difference between a refractive index of the anti-reflection layer 700 and a refractive index of the second electrode 600 is large, a problem occurs where external light passing through the second electrode 600 after being reflected from the inside of the display device does not travel to the inner portion of the anti-reflection layer 700 and is totally reflected from the bottom surface of the anti-reflection layer 700, and thus, in another embodiment of the present inventive concept, because the second interface layer 720 is additionally formed between the anti-reflection layer 700 and the second electrode 600, the refractive index difference between a refractive index of the anti-reflection layer 700 and a refractive index of the second electrode 600 is compensated for, thereby enabling external light to easily travel the inner portion of the anti-reflection layer 700.
The second interface layer 720 may include metal oxide such as silicone oxide, tungsten oxide, or titanium oxide, or may include silicone nitride.
Furthermore, although not shown, in a structure of
According to
On the other hand, according to
The first encapsulation layer 810 and the second encapsulation layer 820 may include the same material, or may include different materials.
Furthermore, although not shown, a first interface layer 710 according to
In this case, the first interface layer 710 is provided to have a refractive index within a range between a refractive index of the anti-reflection layer 700 and a refractive index of the second encapsulation layer 820, and the second interface layer 720 is provided to have a refractive index within a range between a refractive index of the anti-reflection layer 700 and a refractive index of the first encapsulation layer 810.
According to
Furthermore, although not shown, a first interface layer 710 according to
In this case, the first interface layer 710 is provided to have a refractive index within a range between a refractive index of the anti-reflection layer 700 and a refractive index of the hard coating layer 900, and the second interface layer 720 is provided to have a refractive index within a range between a refractive index of the anti-reflection layer 700 and a refractive index of the encapsulation layer 800.
According to
In this case, the second interface layer 720 is provided to have a refractive index within a range between a refractive index of the anti-reflection layer 700 and a refractive index of the hard coating layer 900.
On the other hand,
Hereinafter, only elements which differ from
According to
Furthermore, although not shown, a first interface layer 710 according to
In this case, the first interface layer 710 may be provided to have a refractive index within a range between a refractive index of the anti-reflection layer 700 and a refractive index of the substrate 100, and the second interface layer 720 may be provided to have a refractive index within a range between a refractive index of the anti-reflection layer 700 and a refractive index of the circuit element layer 200, particularly, a gate insulation layer 220.
According to
In this case, the second interface layer 720 may be provided to have a refractive index within a range between a refractive index of the anti-reflection layer 700 and a refractive index of the substrate 100.
Hereinabove, the embodiments of the present inventive concept have been described in more detail with reference to the accompanying drawings, but the present inventive concept is not limited to the embodiments and may be variously modified within a range which does not depart from the technical spirit of the present inventive concept. Therefore, it should be understood that the embodiments described above are exemplary from every aspect and are not restrictive. It should be construed that the scope of the present inventive concept is defined by the below-described claims instead of the detailed description, and the meanings and scope of the claims and all variations or modified forms inferred from their equivalent concepts are included in the scope of the present inventive concept.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2021-0097122 | Jul 2021 | KR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2022/010407 | 7/15/2022 | WO |
