Combined film package in flexible display device and method of manufacturing the same

Abstract

A flexible display device (1) comprising an organic light emitting layer (2) and a thin film encapsulation (TFE) layer (3) providing a combination of encapsulation, polarization and color filtering by embedding a black matrix layer (4) and a color filter layer (5) within an organic layer (33) between a first inorganic layer (31) and a second inorganic layer (32). The black matrix layer (4) preferably comprises a metal layer to additionally form a dielectric-metal-dielectric (DMD) structure in combination with the first inorganic layer (31) and the second inorganic layer (32) to obtain additional flexibility. The black matrix layer (4) preferably further comprises a wire mesh (41) to form a polarizer layer within the TFE layer (3) to improve display performance and reduce display stack thickness.

Description

TECHNICAL FIELD

[0001] The present invention relates to a display apparatus, and more particularly, to a flexible display apparatus. Specifically, the present invention relates to a novel thin film encapsulation layer for a flexible OLED display apparatus and a method of manufacturing the same. BACKGROUND

[0002] With the progress of the information society, various requirements have recently been made on image display on devices. Accordingly, various display apparatuses, such as liquid crystal display (LCD) devices, plasma display panel (PDP) devices, and organic light-emitting display (OLED) devices, are being used and manufactured.

[0003] OLED is a flat light-emitting technology that uses a series of organic thin films between two conductors. When a current is applied, it emits bright light. Thus, OLED is an emissive display that does not require a backlight, and thus is thinner and more efficient than an LCD display that requires a white backlight. OLED display apparatuses have advantages of low energy consumption, high brightness, fast response time, wide viewing angle, light weight, etc., and have been widely used in devices such as mobile communication terminals, personal digital assistants (PDAs), and portable computers. OLED display apparatuses are classified into passive matrix type and active matrix type, and among them, active matrix type OLED display apparatuses drive OLEDs using thin film transistors (TFTs). OLED display modules also require additional layers to achieve durability, user interface, and optical functions. Typically, at least one layer of a cover window (CW), a touch sensor (TS), and a circular polarizer (CP) is included, and these must be laminated with an optically clear adhesive (OCA) or a liquid optically clear adhesive (LOCA) to achieve optimal contrast, brightness, and mechanical durability.

[0004] Since the organic materials in OLED displays are very sensitive to oxygen and moisture, the use of an encapsulation layer is essential to protect the device and ensure the required lifetime. In the early generations of products, OLED displays were rigid, sealed in a glass barrier. However, these early OLED displays could not ensure to provide flexible form factors, which are on the rise. Specifically, there is an increasing demand for display-based consumer electronics, while consumers also tend to use energy-efficient, flexible gadgets.

[0005] To solve this problem, the structure of the display stack was fundamentally redesigned and the concept of flexible displays was developed. In this concept, the main rigid components, i.e. the substrate glass and the cover glass, are replaced by flexible components. The substrate is replaced by a high-temperature resistive polyimide film, while the cover glass is replaced by a thin film encapsulation (TFE).

[0006] The main goal of the TFE layer is to prevent the diffusion of water and oxygen to the OLED layer. Therefore, the TFE layer has very strict requirements in terms of water permeability. Typically, the TFE layer comprises multiple layers, including inorganic and organic layers. In most cases, a 3-layer structure has the best performance, where two inorganic layers are typically deposited by a chemical vapor deposition (CVD) method, hence referred to as "CVD 1" and "CVD 2" layers. These CVD layers, i.e. the inorganic layers, are mainly composed of silicon oxide or nitride, which provide the main barrier performance. The organic layer is mainly an acrylic-based organic compound, which provides flexibility. Another important role of the organic layer is to cover particles. During the deposition of the first CVD layer, some particles of size 3-5 pm can be deposited on the surface. When these particles move, they can mechanically damage the encapsulation layer and cause the OLED display to fail. To avoid the movement of these particles, the first CVD layer is covered by an organic component before the deposition of the second CVD layer. The organic component is typically colorless and has a very defined reflection index to provide the best light from the OLED device.

[0007] The problem that occurs with flexible display panels is that when the laminated structure of the flexible display is bent (bent, folded, rolled, etc.), a displacement is created due to the difference between the inner and outer perimeters. In other words, when the display stack is bent, the distance measured on the outer perimeter is longer than the distance measured on the inner perimeter. Depending on the film properties such as modulus and thickness, two fundamentally different cases (or a mixture of these two cases) can be observed.

[0008] In the first case, when the modulus of the layers are close to each other, the strain distribution is equal and a neutral plan (NP) is formed. The NP means that in this layer the strain is equal to 0. Above the NP tensile strain can be formed, while below the NP compressive strain can be formed. In the case of a single NP, very high strain (stress) can occur in the outermost layers, which leads to thin film deformation and the display panel can crack in the area far from the NP.

[0009] In the second case, the modulus of the layers (films) can be very different, resulting in the formation of multiple NPs in the lamination stack. Although in the latter case the strain on the thin films is significantly reduced, the shear strain in the adhesive layer can become a very big problem. High shear strain leads to delamination, creep and failure of the adhesive layer.

[0010] Another problem can occur when the flexible display is bent (bent, rolled, folded) and the strain in the TFE layer exceeds the critical strain value. The reason is that the TFE comprises thin inorganic layers (mainly SiNx and SiO2, sometimes SiOxNy). The critical strain of these thin films depends on the thickness, but in most cases (0.6 pm to 1 pm) the crack initiation strain is 0.6%. Therefore, if the strain in the TFE layer exceeds 0.6%, the display will crack and fail.

[0011] Another problem of such display devices is that in order to ensure sufficient contrast and avoid the color wash effect, the display stack must include a polarizer (POL) layer. However, this POL layer has a relatively high modulus, thus significantly increasing the stiffness of the flexible display. The POL layer also increases the total thickness, thus can lead to increased shared strain, which can be the cause of the display stack failure. In addition, the POL layer has a low yield point and is prone to cracking, especially at lower temperatures. Although reducing the POL layer thickness helps to solve the stiffness problem, it also results in poor reliability, especially in high temperature and humidity environments.

[0012] These problems limit the widespread use of flexible displays, reduce the yield in the manufacturing process, reduce the reliability, increase the cost and can significantly shorten the life of the flexible display device. Therefore, it becomes imperative to solve these problems and technical solutions are eagerly awaited. SUMMARY

[0013] It is an object to provide an improved display device and a method of manufacturing the same, which overcomes or at least reduces the above-mentioned problems by providing an improved thin film encapsulation scheme.

[0014] The above and other objects are achieved by the features of the independent claims. Further implementation forms are evident from the dependent claims, the description and the figures.

[0015] According to a first aspect, there is provided a display device comprising: a light emitting layer; an encapsulation layer disposed above the light emitting layer; a black matrix layer disposed above the light emitting layer; a color filter layer disposed above the light emitting layer; wherein at least one of the black matrix layer and the color filter layer is embedded within the encapsulation layer.

[0016] Providing a black matrix (BM) layer and a color filter (CF) layer within the display stack allows to eliminate the polarizer (POL) layer from the display device, thus eliminating the above-mentioned problems caused by the POL layer, such as an increase in stiffness and a significant reduction in the yield point. This solution also allows to reduce the overall thickness of the display stack, while improving the mechanical properties of the encapsulation layer itself.

[0017] Eliminating the POL layer, which can absorb 50% of the light, further improves the energy consumption of the display device, since it can achieve the same brightness with 50% less energy consumption of the POL layer. This in turn extends the battery operating time and the general lifetime of the display, especially for OLED devices.

[0018] Furthermore, embedding the BM layer and / or the CF layer within the encapsulation layer can avoid the technical problems related to the washout effect caused by the locking of the light between sub-pixels and the poor contrast, which can arise when replacing the POL layer with a combination of BM+CF layers, while further reducing the overall thickness of the display stack.

[0019] Moving the color filter layer, which is usually embedded in the layers on top of the encapsulation layer, within the encapsulation layer further improves the viewing angle of the display device, thus improving the user experience.

[0020] Therefore, this encapsulation arrangement combines several key functions of the display device (encapsulation, color filtering, polarization) into one compact solution.

[0021] In one embodiment, the encapsulation layer is arranged adjacent to the light emitting layer to ensure a reduction in the overall thickness of the display stack.

[0022] In a possible implementation form of the first aspect, the encapsulation layer is a thin film encapsulation (TFE) layer comprising: a first inorganic layer; a second inorganic layer disposed above the first inorganic layer; an organic layer disposed between the first inorganic layer and the second inorganic layer; wherein the at least one of the black matrix layer and the color filter layer is embedded within the organic layer. Using a TFE layer in the display device ensures an optimal resistance to the diffusion of water and oxygen towards the light emitting layer.

[0023] In an embodiment, the first inorganic layer is an inorganic film comprising any of SiO2, SiNx or Al2O3, thereby ensuring optimal water permeability and mechanical properties.

[0024] In an embodiment, the second inorganic layer is an inorganic film comprising any of SiNx, SiOx, SiNxOy or Al2O3, thereby ensuring optimal water permeability and mechanical properties.

[0025] In a further possible implementation form of the first aspect, the black matrix layer comprises at least one metal layer; the first inorganic layer and the second inorganic layer are both dielectric layers; and the black matrix layer is embedded within the organic layer to combine with the first inorganic layer and the second inorganic layer to form a dielectric-metal-dielectric structure. Embedding at least one metal layer within the TFE structure as a dielectric-metal-dielectric (DMD) structure improves the crack resistance and mechanical durability of the display device by improving the barrier properties, mechanical flexibility and heat dissipation, which are essential requirements for display device packaging, especially for OLED displays.

[0026] In an embodiment, the plurality of metal layers comprises any one or combination of aluminum, silver, titanium, chromium, molybdenum, tungsten and copper, thereby ensuring optimal mechanical and heat resistance properties.

[0027] In a further possible implementation form of the first aspect, the black matrix layer comprises a wire mesh grid arranged to convert a non-polarized light beam into a polarized light beam by transmitting only the vertical component of the non-polarized light beam and absorbing or reflecting the horizontal component of the non-polarized light beam. Using a wire mesh grid can improve the display performance and reduce any issues caused by emitting a standard polarizer layer as described above, by using the black matrix layer as a metal grid polarizer layer that can convert any non-polarized light beam into a light beam with a single linear polarization, reducing light trapping and ambient light reflection.

[0028] In an embodiment, the wire mesh grid is arranged in a grid size of up to 500 nm, and up to 500 nm wide, which ensures optimal performance and reduced ambient light reflection.

[0029] In a further possible implementation form of the first aspect, the display device further comprises a polarizer layer embedded within the encapsulation layer and arranged to cover at least one of the black matrix layer and the color filter layer. Adding a polarizer layer helps to further reduce the issues caused by emitting a standard polarizer layer as described above, by reducing light trapping.

[0030] In another possible implementation form of the first aspect, the polarizer layer is an inorganic layer of high reflective index material, thereby providing a quarter polarizer function.

[0031] In an embodiment, the polarizer layer is arranged with a thickness between 1 nm and 10 nm and made of at least one of TiO2 or Al2O2, or the like, which ensures optimal layer thickness and mechanical properties of the display stack.

[0032] In another possible implementation form of the first aspect, the polarizer layer comprises a colorless polymer with a refractive index between 1.2 and 1.6, which ensures optimal reduced light lock-in and improves display performance.

[0033] In another possible implementation form of the first aspect, the encapsulation layer further comprises a planarization layer covering at least one of the black matrix layer and the color filter layer and forming a planar top surface, thereby ensuring an optimal support surface for a second inorganic (chemical vapor deposition, CVD) layer of the encapsulation layer.

[0034] In an embodiment, the planarization layer comprises a colorless acrylic monomer to ensure optimal optical performance.

[0035] In another possible implementation form of the first aspect, the display device further comprises a base substrate; and a circuitry arranged between the base substrate and the light emitting layer, the circuitry comprising a plurality of thin film transistors, thereby enabling optimal display arrangement for the display device.

[0036] In yet another possible implementation form of the first aspect, the base substrate is a flexible substrate and the display device is a flexible display device, thereby ensuring improved flexibility.

[0037] In an embodiment, the base substrate is made of polyimide, further ensuring optimal mechanical flexibility and strain resistance.

[0038] In another possible implementation form of the first aspect, the light emitting layer comprises a first electrode; a second electrode; and an electroluminescent layer arranged between the first electrode and the second electrode, wherein the first electrode is connected to at least one of the plurality of thin film transistors, which ensures optimal display performance of the device.

[0039] In another possible implementation form of the first aspect, the color filter layer comprises color filters of different colors, wherein adjacent color filters of different colors are in contact with each other, which ensures optimal display performance.

[0040] In a further possible implementation form of the first aspect, the display device further comprises a touch screen panel disposed above the encapsulation layer, thereby enabling additional touch functionality of the display device.

[0041] In a further possible implementation form of the first aspect, the display device further comprises a cover window arranged as an outer layer of the display device, the cover window being connected to any of the encapsulation layers by a pressure sensitive adhesive, or a touch screen panel disposed above the encapsulation layers. This ensures an optimal arrangement of the display stack and mechanical protection.

[0042] In one embodiment, the light emitting layer is an organic light emitting layer, and the display device is an organic light emitting device, which ensures optimal display performance.

[0043] According to a second aspect, there is provided a method of manufacturing a display device, the method comprising forming a light emitting layer; forming an encapsulation layer on the light emitting layer; wherein forming the encapsulation layer comprises forming a pattern of at least one of a black matrix layer and a color filter layer embedded in the encapsulation layer.

[0044] Forming the black matrix (BM) layer and the color filter (CF) layer within the display stack allows to eliminate the polarizer (POL) layer from the display device, thereby eliminating the above mentioned problems caused by the POL layer, such as increased stiffness and significantly reduced yield point. This approach can also reduce the overall thickness of the display stack, while improving the mechanical properties of the encapsulation layer itself.

[0045] Eliminating the POL layer, which can absorb 50% of the light, further improves the energy consumption of the display device, as it can achieve the same brightness at 50% of the energy consumption of the POL layer. This in turn extends the battery operation time and the general lifetime of the display, especially for OLED devices.

[0046] Furthermore, forming the BM layer and / or the CF layer within the encapsulation layer can avoid the technical problems related to the washout effect caused by the locking of the light between sub-pixels and poor contrast, which can occur when replacing the POL layer with a combination of BM+CF layers, while further reducing the overall thickness of the display stack.

[0047] Moving the color filter layer, which is usually embedded on top of the encapsulation layer, within the encapsulation layer further improves the viewing angle of the display device, thereby improving the user experience.

[0048] In a possible implementation form of the second aspect, forming the encapsulation layer comprises forming a first inorganic layer; forming a pattern of a black matrix layer on the first inorganic layer, the pattern comprising gaps; forming a color filter layer by disposing color filters in the gaps; forming an organic layer on top of the layers mentioned above with a flat top surface; forming a second inorganic layer on the flat top surface of the organic layer. By forming the encapsulation layer by forming a pattern of a black matrix with gaps and disposing color filters in the gaps, optimal manufacturing precision and reduced possible failures are ensured. Furthermore, creating a flat top surface of the organic layer provides an optimal support surface for the second inorganic layer.

[0049] In another possible implementation form of the second aspect, forming any of the first inorganic layer and the second inorganic layer comprises chemical vapor deposition until a thickness between 0.1 pm and 6 pm, more preferably between 1 pm and 2 pm, which ensures optimal display stack thickness and mechanical properties.

[0050] In another possible implementation form of the second aspect, forming any of the first inorganic layer and the second inorganic layer comprises atomic layer deposition until a thickness between 20 nm and 200 nm, more preferably between 50 nm and 80 nm, which ensures optimal display stack thickness and mechanical properties.

[0051] In another possible implementation form of the second aspect, forming the pattern of the black matrix layer comprises forming a plurality of metal layers; the color filter layer is a dielectric layer; and, forming the encapsulation layer comprises embedding the black matrix layer and the color filter layer within the encapsulation layer in a dielectric-metal-dielectric arrangement. Embedding a plurality of metal layers within the TFE structure as a dielectric-metal-dielectric (DMD) structure improves the crack resistance and mechanical durability of the display device by improving the barrier properties, mechanical flexibility and heat dissipation, which are essential requirements for the encapsulation of display devices, in particular for OLED displays.

[0052] In another possible implementation form of the second aspect, forming the pattern of the black matrix layer comprises manufacturing a wire mesh arranged to convert a non-polarized light beam into a polarized light beam by transmitting only the vertical component of the non-polarized light beam and absorbing or reflecting the horizontal component of the non-polarized light beam. Using a wire mesh can improve the display performance and reduce any issues caused by emitting a standard polarizer layer as described above by using the black matrix layer as a metal mesh polarizer layer that can convert any non-polarized light beam into a light beam with a single linear polarization, reducing light trapping and ambient light reflection.

[0053] In one embodiment, fabricating the wire mesh includes at least one of direct deposition by selective ALD process, FMM mask deposition, or sputtering followed by etching, which ensures optimal manufacturing precision and reduces display stack thickness.

[0054] In another possible implementation of the second aspect, forming the color filter layer includes material deposition using any one of dyeing, pigment deposition, printing, or electrodeposition methods, up to a thickness of 3-4 pm.

[0055] In one embodiment, forming the color filter layer includes dyeing, wherein the material used to form the color filter includes at least one of gelatin, casein, and synthetic products such as polyvinyl alcohol and polyvinyl pyrrolidone.

[0056] In another possible embodiment, the color filter layer includes pigment deposition, and the material used as the matrix includes any one of acrylic or epoxy acrylate photopolymerizable materials.

[0057] In another possible embodiment, forming the color filter layer includes printing using any one of screen printing, flexographic printing, offset printing, or gravure printing.

[0058] In another possible implementation of the second aspect, forming the encapsulation layer includes forming a polarizer layer, the polarizer layer being arranged to cover the pattern of at least one of the black matrix layer and the color filter layer embedded within the encapsulation layer. Adding the polarizer layer helps to further reduce the problems created by the emission of standard polarizers as described above by reducing light-locking.

[0059] In another possible implementation of the second aspect, the method of fabricating the display device further includes providing a base substrate; forming a circuit between the base substrate and the light emitting layer, the circuit including a plurality of thin film transistors, thereby enabling optimal display arrangement of the display device.

[0060] In another possible implementation of the second aspect, the method of fabricating the display device further includes providing a touch screen panel above the encapsulation layer, thereby enabling additional touch functionality of the display device.

[0061] In another possible implementation of the second aspect, the method of fabricating the display device further includes providing a cover window arranged as an outer layer of the display device, the cover window being attached to any one of the encapsulation layers, or the touch screen panel provided above the encapsulation layers, by a pressure sensitive adhesive. This ensures optimal arrangement and mechanical protection of the display stack layers.

[0062] These and other aspects are evident from one or more of the embodiments described hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0063] Aspects, embodiments, and implementations will be explained in more detail in the following detailed description, with reference to the exemplary embodiments shown in the drawings from which:

[0064] Figure 1 A schematic cross-section of a display device provided by one embodiment of the first aspect is shown;

[0065] Figure 2 A schematic cross-section of a display device provided by another embodiment of the first aspect is shown;

[0066] Figure 3 A schematic cross-section of an encapsulation layer of a display device provided by another embodiment of the first aspect is shown;

[0067] Figure 4 A schematic cross-section of an encapsulation layer of a display device provided by another embodiment of the first aspect is shown;

[0068] Figure 5 A schematic cross-section and a top view of an encapsulation layer of a display device provided by another embodiment of the first aspect is shown;

[0069] Figure 6 A schematic diagram of the functioning of a wire grid of a display device provided by another embodiment of the first aspect is shown;

[0070] Figures 7A to 7D Steps of a method provided by an embodiment of the second aspect are shown. DETAILED DESCRIPTION

[0071] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the relevant teachings. However, it will be apparent to one of ordinary skill in the art that the present application can be practiced without these specific details. In other instances, well-known methods, procedures, systems, components, and / or circuits have not been described in detail in order to avoid unnecessarily obscuring aspects of the present application.

[0072] Furthermore, when a first portion such as a layer, film, region, or plate is provided on a second portion, the first portion can be directly on the second portion, and one or more third portions can be interposed therebetween. Furthermore, when it is stated that a first portion such as a layer, film, region, or plate is formed on a second portion, the surface of the second portion on which the first portion is formed is not limited to the upper surface of the second portion, but can include other surfaces such as a side surface or a lower surface of the second portion. In the following, exemplary embodiments of the present application will be described in detail with reference to the drawings.

[0073] Figure 1An exemplary embodiment of the present application provides a display device 1, comprising a light emitting layer 2 and an encapsulation layer 3 disposed above the light emitting layer 2.

[0074] The display device 1 can be a liquid crystal display (LCD) device, an electrophoretic display (EPD) device, an electrowetting display (EWD) device, or a light-emitting diode (LED) display device. In one embodiment, the light emitting layer 2 is an organic light emitting layer, and the display device 1 is an organic light emitting diode (OLED) display device.

[0075] In one embodiment, the display device 1 is a flexible organic light emitting diode (FOLED) display device, comprising a flexible plastic substrate on which electroluminescent organic semiconductors are deposited, thereby allowing the device to be bent or rolled while still remaining operational.

[0076] The encapsulation layer 3 is used to prevent water and oxygen from diffusing towards the light emitting layer 2. In one embodiment, the encapsulation layer 3 has a water permeation of less than 5*10^-6 grams of water per square meter per day. In one embodiment, the encapsulation layer 3 is disposed adjacent to the light emitting layer 2, while in other possible embodiments, an intermittent layer can be present. The encapsulation layer 3 can itself comprise a plurality of layers, including inorganic layers and organic layers, as described below.

[0077] The display device 1 further comprises a black matrix layer 4 and a color filter layer 5. The color filter layer 5 can comprise Figure 5 Different color filters 51 are shown, where adjacent color filters 51 of different colors can or can not be in contact with each other. The color filters 51 can be used to generate red (R), green (G), and blue (B) pixels.

[0078] The black matrix layer 4 can be arranged in a pattern between individual color filters of the color filter layer 5, and can comprise any material suitable for reducing light leakage, such as chromium or molybdenum.

[0079] Both the black matrix layer 4 and the color filter layer 5 are disposed above the light emitting layer 2, and at least one of the black matrix layer 4 and the color filter layer 5 is embedded within the encapsulation layer 3. In one embodiment, both the black matrix layer 4 and the color filter layer 5 are embedded within the encapsulation layer 3, as shown in Figure 1shown. This allows the elimination of the polarizer (POL) layer from the display device, thus eliminating possible problems caused by the POL layer, such as an increase in the stiffness of the display device 1 and a significant decrease in the yield point, as well as reducing the overall thickness of the display stack and improving the mechanical properties of the encapsulation layer 3 itself. Moreover, the embedding of the black matrix layer 4 and the color filter layer 5 within the encapsulation layer 3 allows to avoid the technical problems related to the washout effect due to the locking of the light between the sub-pixels and the poor contrast, which arise when using a combination of the black matrix layer 4 and the color filter layer 5 in place of the POL layer. Moving the color filter layer 5 within the encapsulation layer 3 further improves the viewing angle of the display device 1, as Figure 3 (shown by the dashed arrow).

[0080] As shown in Figure 1 , the black matrix layer 4 can be arranged in the same plane as the color filter layer 5. The black matrix layer 4 can also be arranged in a different plane from the color filter layer 5, as Figures 2 to 5 shown.

[0081] Figure 2 Another exemplary embodiment of the present application is shown, in which the encapsulation layer 3 is arranged as a thin film encapsulation (TFE) layer comprising a first inorganic layer 31, a second inorganic layer 32 disposed above the first inorganic layer 31, and an organic layer 33 disposed between the first inorganic layer 31 and the second inorganic layer 32. In this embodiment, the black matrix layer 4 and / or the color filter layer 5 are embedded within the organic layer 33. The first inorganic layer 31 can be arranged as an inorganic film containing any of SiO2, SiNx or Al2O3. The second inorganic layer 32 can be arranged as an inorganic film comprising any of SiNx, SiOx, SiNxOy or Al2O3.

[0082] In one embodiment, the encapsulation layer 3 can further comprise a polarizer layer 6 arranged to cover at least one of the black matrix layer 4 and / or the color filter layer 5. The polarizer layer 6 can be an inorganic layer of high refractive index material (e.g. TiO2 or Al2O2, etc.) to provide a quarter-polarizer function. The polarizer layer 6 can be arranged within the encapsulation layer 3 with a thickness of between 1 nm and 10 nm. In one embodiment, the polarizer layer 6 comprises a colorless polymer with a refractive index between 1.2 and 1.6.

[0083] In one embodiment, the encapsulation layer 3 can further comprise a planarization layer 7 covering at least one of the black matrix layer 4 and the color filter layer 5 and forming a planar top surface, as Figure 7D shown. The planarization layer 7 can comprise a colorless acrylic monomer for optimal optical performance.

[0084] As shown in Figure 2 and Figure 3As shown, the display device 1 can further include a base substrate 8 and a circuit 9 arranged between the base substrate 8 and the light emitting layer 2.

[0085] The base substrate 8 is not particularly limited to a specific material as long as the material is capable of functioning as the base substrate 8. For example, the base substrate 8 can be formed of an insulating material such as glass, plastic, or crystal. An organic polymer used to form the base substrate 8 can include polyimide (PI), polycarbonate (PC), polyethyeleneterepthalate (PET), polyethylene (PE), polypropylene (PP), polysulphone (PSF), methylmethacrylate (PMMA), triacetyl cellulose (TAC), cyclo-olefin polymer (COP), and cyclo-olefin copolymer (COC). The base substrate 8 can be adequately selected in consideration of mechanical strength, thermal stability, transparency, surface roughness, operability, waterproof performance, and the like.

[0086] In a possible embodiment, the base substrate 8 can be a flexible substrate that enables the display device 1 to be used as a flexible display device 1. In one embodiment, the base substrate 8 can be made of polyimide.

[0087] As Figure 3 further shown, the circuit 9 can include a plurality of thin film transistors 10, and the light emitting layer 2 can include a first electrode 21, a second electrode 22, and an electroluminescent layer 23 arranged between the first electrode 21 and the second electrode 22. As Figure 3 shown, the first electrode 21 can be connected to at least one of the thin film transistors 10.

[0088] As Figure 3As shown in FIG. 1, the display device 1 can further include a touch screen panel 11 disposed above the encapsulation layer 3 and a cover window 12 disposed as an outer layer of the display device 1. The touch screen panel 11 can recognize a user’s touch, a user’s proximity touch, an object (e.g., a stylus)’s touch, or an object’s proximity touch. The proximity touch can mean a phenomenon in which the touch screen panel 11 recognizes a position where a user or an object approaches the touch screen panel 11 as a touch even though the user or the object does not directly touch the touch screen panel 11. The touch screen panel 11 can be disposed on the thin film encapsulation layer (TFE) 3 at least partially through a transfer process. In an embodiment, a detection electrode of the touch screen panel 11 can be formed through a transfer process.

[0089] The cover window 12 can be connected to any one or both of the encapsulation layer 3 and the touch screen panel 11 through a pressure sensitive adhesive (PSA) 13.

[0090] Figure 4 Another exemplary embodiment of the present application is shown in which the black matrix layer 4 includes at least one metal layer. In a possible embodiment, the black matrix layer 4 can include any one or a combination of aluminum, silver, titanium, chromium, molybdenum, tungsten, and copper layers.

[0091] In the present embodiment, both the first inorganic layer 31 and the second inorganic layer 32 are arranged as dielectric layers, and the black matrix layer 4 is embedded within the organic layer 33 to form a dielectric-metal-dielectric (DMD) structure in combination with the first inorganic layer 31 and the second inorganic layer 32, which improves the crack resistance and mechanical durability of the display device 1 by improving the barrier properties, mechanical flexibility, and heat dissipation, which are essential requirements for encapsulation of the display device 1, particularly for OLED displays.

[0092] Figure 5 Another exemplary embodiment of the present application is shown in which the black matrix layer 4 includes a wire mesh 41 arranged to convert a non-polarized light beam 14 into a polarized light beam 15 by transmitting only a vertical component of the non-polarized light beam 14 and absorbing or reflecting a horizontal component of the non-polarized light beam 14. This function of the wire mesh 41 arrangement of the black matrix layer 4 is further shown in Figure 6 As further shown in FIG. 1, a non-polarized light beam 14 is shown, a horizontal component of which is absorbed and / or reflected by the wire mesh 41 to produce a polarized light beam 15.

[0093] In one embodiment, the wire mesh 41 is arranged in a grid size of up to 500 nm, wide up to 500 nm, to achieve the best polarization effect.

[0094] In one possible embodiment, the features shown and explained in Figures 1 to 5 the TFE encapsulation layer 3, such that the black matrix layer 4 in combination with the first inorganic layer 31 and the second inorganic layer 32 forms a DMD structure, and the black matrix layer 4 is further arranged in the wire mesh 41 to convert the unpolarized light beam 14 into a polarized light beam 15, thereby providing the TFE encapsulation layer 3 with a polarizing function, in addition to reducing the thickness and improving the mechanical and optical properties.

[0095] Figures 7A to 7D Steps of a method of manufacturing the display device 1 according to another exemplary embodiment of the application are shown. For the sake of simplicity, steps and features that are identical or similar to corresponding steps and features previously described or shown herein are denoted with the same reference numerals as previously used.

[0096] Figure 7A A first manufacturing step is shown, in which the light emitting layer 2 is first formed, and then the encapsulation layer 3 is formed on the light emitting layer 2. In particular, as a first step of forming the encapsulation layer 3, the first inorganic layer 31 is formed on the light emitting layer 2.

[0097] In one embodiment, forming the first inorganic layer 31 comprises chemical vapor deposition (CVD) until a thickness between 0.1 pm and 6 pm, more preferably between 1 pm and 2 pm. In another embodiment, forming the first inorganic layer 31 comprises atomic layer deposition (ALD) until a thickness between 20 nm and 200 nm, more preferably between 50 nm and 80 nm.

[0098] In a subsequent step of forming the encapsulation layer 3, shown in Figure 7B the pattern of the black matrix layer 4 is formed on the first inorganic layer 31, the pattern comprising the gaps 42, as shown in Figure 5 The step of forming the pattern of the black matrix layer 4 can comprise direct deposition by selective ALD process, FMM mask deposition, or sputtering followed by etching.

[0099] In one embodiment, forming the pattern of the black matrix layer 4 comprises forming a plurality of metal layers. In this embodiment, also shown in Figure 4 the first inorganic layer 31 and the second inorganic layer 32 are both dielectric layers, and forming the encapsulation layer 3 comprises embedding the black matrix layer 4 within the encapsulation layer 3 in a dielectric-metal-dielectric (DMD) arrangement with the first inorganic layer 31 and the second inorganic layer 32 to improve the crack resistance and mechanical durability of the display device 1.

[0100] In another possible embodiment, optionally in combination with the above embodiments of the dielectric-metal-dielectric DMD arrangement, the patterning of the black matrix layer 4 includes fabricating a wire grid 41 arranged to convert the non-polarized light beam 14 into a polarized light beam 15 by transmitting only the vertical component of the non-polarized light beam 14 and absorbing or reflecting the horizontal component of the non-polarized light beam 14, as shown in FIG. 4. Figure 6 In one possible embodiment, the wire grid 41 is formed as a grid size up to 500 nm and as wide as 500 nm for optimal polarization performance.

[0101] In a subsequent step of forming the encapsulation layer 3, as shown in FIG. 5, the color filter layer 5 is formed by disposing color filters 51 in the previously formed gaps 42 of the black matrix layer 4. The gaps 42 can be formed as part of the wire grid 41. Forming the color filter layer 5 can include material deposition using any one of dyeing, pigment deposition, printing, or electrodeposition methods, up to a thickness of 3-4 pm. Figure 7C

[0102] In embodiments where forming the color filter layer 5 includes dyeing, the material used to form the color filters 51 can include at least one of gelatin, casein, and synthetic products such as polyvinyl alcohol (PVA) and polyvinyl pyrrolidone.

[0103] In embodiments where forming the color filter layer 5 includes pigment deposition, the material used as the matrix can include any one of acrylic or epoxy acrylate photopolymerizable materials.

[0104] In embodiments where forming the color filter layer 5 includes printing, any one of screen printing, flexographic printing, offset printing, or gravure printing can be used.

[0105] In a subsequent step of forming the encapsulation layer 3, as shown in FIG. 6, an organic layer 33 having a planar top surface is formed on top of the preceding layers (the black matrix layer 4 and the color filter layer 5). In one embodiment, the planar top surface is arranged as a planarization layer 7 and includes a colorless acrylic monomer that is planar on its top surface. Figure 7D In one embodiment, forming the encapsulation layer 3 can further include the step of forming a polarizer layer 6 as described in detail above, arranged to cover the pattern of the black matrix layer 4 and the color filter layer 5 embedded within the encapsulation layer 3.

[0106]

[0107] ​​Finally, a second inorganic layer 32 is formed on the planar top surface of the organic layer 33. In one embodiment, forming the second inorganic layer 32 includes chemical vapor deposition (CVD) until a thickness between 0.1 pm and 6 pm, more preferably between 1 pm and 2 pm. In another embodiment, forming the second inorganic layer 32 includes atomic layer deposition (ALD) until a thickness between 20 nm and 200 nm, more preferably between 50 nm and 80 nm.

[0108] As shown in FIG. 1, the display device 1 can further include a cover window 12 disposed above the encapsulation layer 3. The cover window 12 can be arranged as an outer layer of the display device 1. The cover window 12 can be connected to the encapsulation layer 3 and / or the touch screen panel 11 disposed above the encapsulation layer 3 by a pressure sensitive adhesive (PSA) 13. Figure 3 As shown in FIG. 1, the display device 1 can further include a cover window 12 disposed above the encapsulation layer 3. The cover window 12 can be arranged as an outer layer of the display device 1. The cover window 12 can be connected to the encapsulation layer 3 and / or the touch screen panel 11 disposed above the encapsulation layer 3 by a pressure sensitive adhesive (PSA) 13.

[0109] In another embodiment, as shown in FIG. 1, the touch screen panel 11 can be disposed above the encapsulation layer 3. Figure 3

[0110] In another embodiment, as shown in FIG. 1, the touch screen panel 11 can be disposed above the encapsulation layer 3. Figure 3

[0111] Various aspects and implementations have been described herein with regard to various embodiments. However, other variations of the disclosed embodiments can be understood and implemented by those skilled in the art upon study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word only or one does not exclude a plurality. A single processor or other unit can fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. A computer program can be stored / distributed on a suitable medium, such as an optical storage medium or a solid-state storage medium supplied together with or as part of other hardware, but can also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems.

[0112] The reference signs used in the claims should not be construed as limiting the scope.​​

Claims

1. A display device (1), characterized in that It comprises: a light emitting layer (2); an encapsulation layer (3) disposed above the light emitting layer (2); a black matrix layer (4) disposed above the light emitting layer (2); a color filter layer (5) disposed above the light emitting layer (2); wherein the black matrix layer (4) and the color filter layer (5) are both embedded in the encapsulation layer (3); the encapsulation layer (3) is a thin film encapsulation layer, the thin film encapsulation layer comprising: a first inorganic layer (31); a second inorganic layer (32) disposed above the first inorganic layer (31); an organic layer (33) disposed between the first inorganic layer (31) and the second inorganic layer (32); wherein the black matrix layer (4) and the color filter layer (5) are both embedded in the organic layer (33); the black matrix layer (4) comprises at least one metal layer; the first inorganic layer (31) and the second inorganic layer (32) are both dielectric layers; the black matrix layer (4) is embedded in the organic layer (33) to form a dielectric-metal-dielectric structure in combination with the first inorganic layer (31) and the second inorganic layer (32); the color filter layer (5) comprises different color filters 51, the different color filters 51 being located in the same layer; the black matrix layer (4) comprises a metal wire mesh (41) arranged to convert a non-polarized light beam (14) into a polarized light beam (15) by transmitting only the vertical component of the non-polarized light beam (14) and absorbing or reflecting the horizontal component of the non-polarized light beam (14).

2. The display device (1) according to claim 1, characterized in that It also comprises: a polarizer layer (6) embedded in the encapsulation layer (3) and arranged to cover the at least one of the black matrix layer (4) and the color filter layer (5).

3. The display device (1) according to claim 2, characterized in that The polarizer layer (6) is an inorganic layer of high refractive index material.

4. The display device (1) according to claim 2, characterized in that The polarizer layer (6) comprises a colorless polymer having a refractive index between 1.2 and 1.

6.

5. The display device (1) according to any one of claims 1 to 4, characterized in that The encapsulation layer (3) further comprises: a planarization layer (7) covering at least one of the black matrix layer (4) and the color filter layer (5) and forming a planar top surface.

6. The display device (1) according to any one of claims 1 to 4, characterized in that It also comprises: a base substrate (8); a circuit (9) arranged between the base substrate (8) and the light emitting layer (2), the circuit (9) comprising a plurality of thin film transistors (10).

7. The display device (1) according to claim 6, characterized in that The base substrate (8) is a flexible substrate, and the display device (1) is a flexible display device (1).

8. The display device (1) according to any of claims 1 to 4, characterized in that It also comprises: a touch screen panel (11) disposed above the encapsulation layer (3).

9. The display device (1) according to any of claims 1 to 4, characterized in that It also comprises: a cover window (12) arranged as an outer layer of the display device (1), the cover window (12) being connected to any one of the encapsulation layers (3) or a touch screen panel (11) disposed above the encapsulation layers (3) by a pressure-sensitive adhesive (13).

10. A method of manufacturing a display device (1), characterized by The method comprises: forming a light emitting layer (2); forming an encapsulation layer (3) on the light emitting layer (2); wherein forming the encapsulation layer (3) comprises forming a pattern of a black matrix layer (4) and a color filter layer (5) embedded in the encapsulation layer (3); forming the encapsulation layer (3) comprises: forming a first inorganic layer (31); forming a pattern of a black matrix layer (4) on the first inorganic layer (31), the pattern comprising gaps (42); forming a color filter layer (5) by providing color filters (51) in the gaps (42); forming an organic layer (33) with a flat top surface on top of the black matrix layer (4); forming a second inorganic layer (32) on the flat top surface of the organic layer (33); forming the pattern of the black matrix layer (4) comprises forming a plurality of metal layers; the first inorganic layer (31) and the second inorganic layer (32) are both dielectric layers; wherein forming the encapsulation layer (3) comprises embedding the black matrix layer (4) within the encapsulation layer (3) in a dielectric-metal-dielectric arrangement with the first inorganic layer (31) and the second inorganic layer (32); the color filter layer (5) comprises color filters 51 of different colors, the color filters 51 of different colors being located in the same layer; forming the pattern of the black matrix layer (4) comprises manufacturing a wire grid (41) arranged to convert a non-polarized light beam (14) into a polarized light beam (15) by transmitting only a vertical component of the non-polarized light beam (14) and absorbing or reflecting a horizontal component of the non-polarized light beam (14).

11. The method of claim 10, wherein, forming any of the first inorganic layer (31) and the second inorganic layer (32) comprises chemical vapor deposition until a thickness between 0.1 μm and 6 μm.

12. The method of claim 10, wherein, forming any of the first inorganic layer (31) and the second inorganic layer (32) comprises atomic layer deposition until a thickness between 20 nm and 200 nm.

13. The method according to any one of claims 10 to 12, characterized in that, forming the color filter layer (5) comprises material deposition using any of a dyeing, a pigment deposition, a printing or an electrodeposition method until a thickness of 3 μm to 4 μm.

14. The method of claim 10, wherein, forming the encapsulation layer (3) comprises: forming a polarizer layer (6) arranged to cover the pattern of at least one of a black matrix layer (4) and a color filter layer (5) embedded in the encapsulation layer (3).

15. The method according to any one of claims 10 to 12, characterized in that, further comprising: providing a base substrate (8); forming a circuit (9) between the base substrate (8) and the light emitting layer (2), the circuit (9) comprising a plurality of thin film transistors (10).

16. The method of any one of claims 10-12, wherein, further comprising: providing a touch screen panel (11) above the encapsulation layer (3).

17. The method of any one of claims 10-12, wherein, further comprising: providing a cover window (12) arranged as an outer layer of the display device (1), the cover window (12) being connected to any of the encapsulation layer (3) or the touch screen panel (11) provided above the encapsulation layer (3) by a pressure sensitive adhesive (13).

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