CN107086240B - Organic electroluminescent display device, preparation method thereof, mask and display device - Google Patents

Abstract

The invention provides an organic electroluminescent display device, a preparation method thereof, a mask and a display device, wherein the organic electroluminescent display device comprises: a cathode; an anode; and the organic functional layer is filled between the cathode and the anode, wherein the first surface of the cathode close to the organic functional layer is set to converge light to the light emergent direction of the organic electroluminescent display device. The organic electroluminescent display device reflects light rays irradiated from the light emitting layer to the light emitting direction and has certain convergence effect on the reflected light rays, so that the light emitting efficiency of the OLED device is improved, and the service life of the light emitting material is prolonged.

Description

Organic electroluminescent display device, preparation method thereof, mask and display device

Technical Field

The invention relates to the technical field of display, in particular to an organic electroluminescent display device, a preparation method thereof and a display device.

Background

Organic Light-Emitting Display (OLED) has advantages of self-luminescence, fast response, high brightness, bright color, Light weight, and thin profile, and is considered as the next generation Display technology. The self-luminous element, i.e. the OLED device, is mainly composed of an anode layer, an organic material functional layer (usually including functional layers such as an electron transport layer, a light emitting layer, and a hole transport layer), and a cathode layer, which are sequentially disposed away from a substrate. The OLED device may be classified into two types of a bottom emission type (i.e., emitting light downward with respect to a substrate) and a top emission type (i.e., emitting light upward with respect to a substrate) according to a light emitting direction.

However, as shown in fig. 1, since the bottom-emission OLED device has a downward light emitting direction, if light is irradiated into the driving transistor below, the light leakage phenomenon of the driving transistor may occur, and the display performance is affected, so that there is a certain distance between the projection of the opening portion 02 of the Pixel Defining Layer (PDL)01 for defining the size of the light emitting area of each bottom-emission OLED device on the substrate and the projection of the area where the driving transistor is located on the substrate, that is, the opening portion of the PDL is located away from the driving transistor, and thus, when the light emitted from the organic functional layer 16 is irradiated into the reflective layer of the top metal cathode 15, the light is reflected in all directions of the bottom, including lateral propagation in the transparent film layer, and the like, and thus, the light emitting efficiency of the bottom-emission OLED device is limited, the lifetime loss of the luminescent material in an OLED device is large.

Thus, current OLED devices remain to be improved.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. To this end, an object of the present invention is to provide an organic electroluminescent display device (i.e., OLED device) having advantages of increasing the light extraction efficiency of the OLED device or extending the lifespan of a light emitting material.

In one aspect of the present invention, the present invention provides an organic electroluminescent display device. According to an embodiment of the present invention, the organic electroluminescent display device includes: a cathode; an anode; and the organic functional layer is filled between the cathode and the anode, wherein the first surface of the cathode close to the organic functional layer is set to converge light to the light emergent direction of the organic electroluminescent display device. The inventor finds that the organic electroluminescent display device reflects the light irradiated from the light-emitting layer to the light-emitting direction and has certain convergence effect on the reflected light, so that the light-emitting efficiency of the OLED device is increased, and the service life of the light-emitting material is prolonged.

According to an embodiment of the invention, the first surface is convex in a direction away from the organic functional layer.

According to an embodiment of the present invention, the first surface is formed as a curved surface protruding toward a direction away from the organic functional layer.

According to an embodiment of the present invention, the first surface includes a central plane and a peripheral curved surface disposed around and contiguous to the central plane, wherein the peripheral curved surface gradually approaches the central plane in a direction away from the anode.

According to some embodiments of the invention, the organic functional layer may include a light emitting layer; according to some embodiments of the present invention, the organic functional layer includes an electron transport layer, a light emitting layer, and a hole transport layer sequentially stacked in a direction from the cathode toward the anode; according to some embodiments of the present invention, the organic functional layer includes an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, and a hole injection layer, which are sequentially stacked in a direction from the cathode toward the anode; wherein the surface of at least one of the electron injection layer, the electron transport layer, the light-emitting layer, the hole transport layer and the hole injection layer, which is close to the cathode, is matched with the first surface.

According to the embodiment of the invention, the focus of the light convergence is located on the light-emitting surface of the organic electroluminescent display device.

In another aspect of the present invention, a display device is provided. According to an embodiment of the present invention, the display apparatus includes the organic electroluminescent display device described above. It will be understood by those skilled in the art that the display device has all the features and advantages of the organic electroluminescent display device described above, and thus, a detailed description thereof is omitted.

In still another aspect of the present invention, there is provided a mask for fabricating an organic electroluminescent display device, the mask including a mask body provided with a plurality of opening portions having opening areas gradually decreasing from a center of the mask body in a central line direction of the mask body according to an embodiment of the present invention. The OLED organic material functional film with the arc-shaped section can be manufactured by using the mask, and the thickness of the film is gradually reduced from the middle area to the edge area.

In yet another aspect of the present invention, the present invention provides a method of fabricating an organic electroluminescent display device. According to an embodiment of the invention, the method comprises: forming an anode; forming an organic functional layer on one side of the anode; a cathode is formed on the side of the organic functional layer remote from the anode. And the cathode is arranged close to the first surface of the organic functional layer and converges light rays towards the light emergent direction of the organic electroluminescent display device. The inventor finds that the organic electroluminescent display device prepared by the method can reflect light irradiated from the luminescent layer to the light-emitting direction and has certain gathering effect on the reflected light, so that the light-emitting efficiency of the OLED device is increased, and the service life of the luminescent material is prolonged.

According to an embodiment of the present invention, the organic functional layer is formed using the aforementioned reticle.

Drawings

Fig. 1 is a schematic view of a prior art bottom emission type OLED device structure.

Fig. 2 shows a schematic structural diagram of an OLED device according to one embodiment of the present invention.

Fig. 3A and 3B show schematic structural views of an OLED device according to still another embodiment of the present invention.

Fig. 4A to 4D show schematic structural views of an OLED device according to another embodiment of the present invention.

Fig. 5 shows a schematic structural diagram of an OLED device according to yet another embodiment of the present invention.

FIG. 6 is a schematic diagram of a reticle structure according to an embodiment of the present invention.

FIG. 7 is a schematic cross-sectional view of the reticle of FIG. 6 taken along line AB.

Fig. 8 shows a schematic flow diagram of a method of making an OLED device according to an embodiment of the invention.

Reference numerals:

01: pixel defining layer 02: opening portion 1 of pixel defining layer: substrate 2: the gate insulating layer 3: interlayer insulating layers 4, 5: TFT 6: passivation layer 7: the flat layer 8: pixel defining layer 9: anode 10: hole injection layer 11: hole transport layer 12: light-emitting layer 13: electron transport layer 14: electron injection layer 15: cathode 16: organic functional layer 17: first surface 171 of the cathode: center plane 172: peripheral curved surface 40: drain electrode 001: transmission region 002: impermeable region 003: grid hollowed-out area 004: grid non-hollowed-out area

Detailed Description

The following describes embodiments of the present invention in detail. The following examples are illustrative only and are not to be construed as limiting the invention. The examples, where specific techniques or conditions are not indicated, are to be construed according to the techniques or conditions described in the literature in the art or according to the product specifications. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available.

In one aspect of the present invention, the present invention provides an organic electroluminescent display device. According to an embodiment of the present invention, referring to fig. 2, the organic electroluminescent display device includes: a cathode 15; an anode 9; and an organic functional layer 16, wherein the organic functional layer 16 is filled between the cathode 15 and the anode 9, and the first surface 17 of the cathode 15 close to the organic functional layer 16 is arranged to converge light to the light-emitting direction of the organic electroluminescent display device. The inventor finds that the organic electroluminescent display device reflects the light irradiated from the organic functional layer to the light-emitting direction and has certain convergence effect on the reflected light, so that the light-emitting efficiency of the OLED device is increased, and the service life of the light-emitting material is prolonged.

According to the embodiment of the present invention, the specific shape of the first surface is not particularly limited as long as the light can be efficiently converged toward the light emitting direction of the OLED device, and those skilled in the art can flexibly select the shape according to actual needs. In some embodiments of the present invention, the first surface is convex in a direction away from the organic functional layer. Therefore, for the light emitted from the organic functional layer, the first surface can be equivalent to a concave mirror, and the light is reflected towards the OLED device and has a convergence effect on the light, so that the utilization rate of the light can be improved, and the service life of the organic light-emitting material can be prolonged.

According to the embodiment of the present invention, the specific shape of the convex surface is also not particularly limited as long as the requirement of converging light is satisfied. In some embodiments of the present invention, referring to fig. 2, the first surface 17 is formed as a curved surface that is convex toward a direction away from the organic functional layer 16. Therefore, for the light emitted from the organic functional layer, the first surface can be equivalent to a concave mirror, and the light is reflected towards the OLED device and has a convergence effect on the light, so that the utilization rate of the light can be improved, and the service life of the organic light-emitting material can be prolonged. In other embodiments of the present invention, referring to fig. 3A and 3B, the first surface 17 includes a central plane 171 and a peripheral curved surface 172 disposed around and contiguous with the central plane, wherein the peripheral curved surface 172 gradually approaches the central plane 171 in a direction away from the anode 9. Therefore, the first surface reflects the light emitted by the organic functional layer to the light-emitting direction and has a convergence effect on the light, so that the light utilization rate can be effectively improved, and the service life of the organic light-emitting material is prolonged. According to the embodiment of the present invention, the shape of the peripheral curved surface 172 may be a convex surface (fig. 3A) protruding in a direction away from the anode, or may be an inclined plane (fig. 3B), and of course, those skilled in the art can understand that the specific shape of the peripheral curved surface is not limited to the case shown in fig. 3A and 3B, as long as it can effectively play a role of converging light rays in the light outgoing direction, and those skilled in the art can design according to actual needs.

According to an embodiment of the present invention, a material forming the cathode is not particularly limited, and one skilled in the art can flexibly select it as desired. In some embodiments of the invention, a metallic material is selected to form the cathode, including, for example, but not limited to, silver, magnesium, aluminum, or alloys thereof. Therefore, the light guide plate has good light guide performance and a good reflection function on light, so that the light convergence effect can be further improved, the light utilization rate is improved, and the service life of a luminescent material is prolonged.

According to the embodiment of the invention, in order to ensure the conductivity of the cathode and the use effect of the OLED device, the cathode is arranged on the metal layer with uniform thickness, so that the cathode is not easy to crack and the like, the conductivity effect is ideal, the cathode resistance is small, and the use performance of the OLED device is favorably improved.

According to the embodiment of the present invention, the specific structure of the organic functional layer is also not particularly limited as long as it can be controlled to emit specific light by applying appropriate current thereto through the cathode and the anode. In some embodiments of the present invention, referring to fig. 4A, the organic functional layer 16 may include the light emitting layer 12. In other embodiments of the present invention, referring to fig. 4B, the organic functional layer 16 may include an electron transport layer 13, a light emitting layer 12, and a hole transport layer 11 sequentially stacked along the cathode 15 toward the anode 9. In still other embodiments of the present invention, referring to fig. 4C, the organic functional layer 16 may include an electron injection layer 14, an electron transport layer 13, a light emitting layer 12, a hole transport layer 11, and a hole injection layer 10, which are sequentially stacked in a direction toward the anode 9 from the cathode 15. Here, referring to fig. 4A to 4D, a surface of at least one of the electron injection layer 14, the electron transport layer 13, the light emitting layer 12, the hole transport layer 11, and the hole injection layer 10 near the cathode 15 matches the first surface 17. Therefore, current can be effectively applied to the organic functional layer through the cathode and the anode to control the light emission of the organic functional layer, so that effective display can be realized, and the surface, close to the cathode 15, of at least one of the electron injection layer 14, the electron transport layer 13, the light emitting layer 12, the hole transport layer 11 and the hole injection layer 10 is matched with the first surface 17, so that the first surface of the cathode can be formed into a target shape and has a function of converging light rays in the light outgoing direction. It will be understood by those skilled in the art that the specific shapes of the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer and the hole injection layer are not limited to those shown in fig. 4A to 4D, and those skilled in the art can flexibly adjust as needed, and take the structure of the organic functional layer including the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer and the hole injection layer as an example, the surface near the cathode of any one, two, three, four or five of the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer and the hole injection layer can be simultaneously formed as a convex surface protruding in a direction away from the anode, fig. 4C and 4D respectively show the case where only the surface near the cathode of the electron injection layer 14 is formed as a convex surface and the surfaces near the cathode of the electron injection layer 14 and the electron transport layer 13 are formed as convex surfaces, other setting modes can be flexibly selected by those skilled in the art according to needs, and are not described in detail herein.

According to the embodiment of the present invention, the material for forming the organic functional layer is not particularly limited, and those skilled in the art can flexibly select the material according to the needs as long as the usage requirements of the OLED device are met. For example, the light emitting layer may be formed of an organic small molecule material such as anthracene derivatives, an organic polymer material such as PPV and derivatives thereof, and the materials of the electron injection layer, the electron transport layer, the hole transport layer, and the hole injection layer may be selected from any materials known in the art to be used for corresponding layer structures, which are not described herein in detail.

According to the embodiment of the present invention, the material forming the anode is also not particularly limited, and may be selected by those skilled in the art as needed, for example, but not limited to, a transparent conductive oxide such as Indium Tin Oxide (ITO), a conductive polymer, nitric acid-treated multi-layer graphene, a carbon tube, and the like. Therefore, the conductive film has good light transmittance while ensuring good conductive performance, and is beneficial to improving the display effect.

According to an embodiment of the present invention, referring to fig. 5, the OLED device may further include an array substrate disposed thereunder, the array substrate including a substrate 1, a gate insulating layer 2, an etch barrier layer (interlayer insulating layer) 3, TFTs 4 and 5, a passivation protection layer 6, a planarization layer 7, a pixel defining layer 8, and an OLED transparent anode 9, wherein the OLED transparent anode 9 is electrically connected to the drain 40 of the TFT4 through a via. Because the prepared bottom TFT array substrate has a step difference, and the OLED device generally has an anode, a cathode, and an organic functional layer, and the above structures are required to be sequentially formed on a relatively flat surface when the OLED device is prepared, a flat layer 7 is further required to be disposed on the passivation protection layer 6, and the flat layer may be made of an insulating material with a high transmittance, such as resin, and the thickness of the flat layer may be 2 to 20 micrometers. As can be seen from fig. 5, with the OLED device of the present invention, light emitted from the organic functional layer is reflected by the first surface of the cathode and then converged, and light emitted toward the TFT is greatly reduced, thereby significantly improving the phenomenon of photo-generated current and improving the display performance, and the distance between the projection of the pixel defining layer on the substrate and the TFT can be significantly reduced, thereby increasing the light emitting area and improving the display effect.

According to the embodiment of the present invention, the first surface of the cathode is not particularly limited in the degree of convergence of light as long as the convergence can be exerted. In some embodiments of the present invention, different shapes of the first surface are arranged to generate different degrees of convergence on light, for example, in some embodiments, light can be converged toward the light emitting direction, but the converged light does not converge to a point; in other embodiments, the converging light rays may intersect at a point, i.e., have a focal point. When the light can converge on the focus, the position of the focus is not particularly limited, and those skilled in the art can flexibly select the display effect according to the needs. In some embodiments of the present invention, referring to fig. 5, the focus a of the light convergence may be located on the light emitting surface of the OLED device. Therefore, the displayed image has high definition, and the display effect is further improved.

It should be noted that fig. 1 to fig. 5 are schematic cross-sectional views of a sub-pixel unit, where a plurality of sub-pixel units form a pixel unit, and a plurality of pixel units are arranged in an array on the OLED device. For example, a pixel unit includes three sub-pixels R, G and B, and fig. 1 to 5 are schematic cross-sectional views of a sub-pixel unit, i.e., R, G or B.

In another aspect of the present invention, a display device is provided. According to an embodiment of the present invention, the display apparatus includes the organic electroluminescent display device described above. The inventor finds that the display device has high light utilization rate and long service life, and has large light-emitting area and ideal display effect. It will be understood by those skilled in the art that the display device has all the features and advantages of the organic electroluminescent display device described above, and thus, a detailed description thereof is omitted.

According to the embodiment of the present invention, the specific type of the display device is not particularly limited, and may be any device or apparatus having a display function in the art, for example, including but not limited to a mobile phone, a tablet computer, a computer monitor, a game machine, a television, a display screen, a wearable apparatus, and other life or household appliances having a display function.

Of course, it can be understood by those skilled in the art that the display device of the present invention may include necessary structures and components of a conventional display device in addition to the organic electroluminescent display device described above, and it is exemplified by a mobile phone, and may further include structures and components of a conventional mobile phone such as a touch screen, a housing, a CPU, a camera module, a fingerprint recognition module, a sound processing system, and the like in addition to the OLED device of the present invention.

In still another aspect of the present invention, there is provided a mask for fabricating an organic electroluminescent display device, the mask including a mask body provided with a plurality of opening portions having opening areas gradually decreasing from a center of the mask body in a central line direction of the mask body according to an embodiment of the present invention. The OLED organic material functional film layer with thick middle and thin periphery can be manufactured by using the mask plate, and the thickness of the film layer is gradually reduced from the middle area to the edge area.

According to some embodiments of the present invention, referring to fig. 6, the reticle body includes a middle transmissive region 001 and an edge non-transmissive region 002, wherein the middle transmissive region 001 is in a grid shape, the grid transmissive region 001 includes a grid hollowed-out region 003, i.e. an opening, and a grid non-hollowed-out region 004 at the edge of the grid hollowed-out region 003, during evaporation, organic material particles may pass through the grid hollowed-out region 003 to reach the evaporation substrate, thereby implementing growth of an organic functional layer, and may reach below the grid non-hollowed-out region 004 through diffusion of a material, thereby forming a continuous organic functional layer. The inventor finds that the surface of the organic functional layer, which is close to the cathode and prepared by the mask plate disclosed by the invention, can form a convex surface which is convex towards the direction far away from the anode, so that the surface of the cathode, which is close to the organic functional layer, forms a corresponding convex surface when the cathode is formed, light emitted by the organic functional layer is reflected and converged, the light utilization rate is improved, the service life of the organic light-emitting material is prolonged, and the surface of the formed organic functional layer is smooth, so that the preparation of the cathode and the reflection of light are facilitated.

According to the embodiment of the present invention, the shape, the specific size of the opening area, the distribution, and the like of the opening are not particularly limited as long as the area of the opening is gradually reduced from the center to the periphery of the mask body, and the organic function with a thick middle and a thin periphery can be formed, and those skilled in the art can flexibly design the opening according to the processing conditions, the specific requirements of the required organic functional layer, and the like. In some embodiments of the present invention, a cross-sectional view of the mask along the direction AB in fig. 6 is shown in fig. 7, where the distance between the grid non-hollowed-out regions 004 at the edges of the grid hollowed-out regions 003 gradually decreases from the middle to the two sides, that is, the width of the most central grid hollowed-out region is d1, and the widths of the grid hollowed-out regions at the two sides are sequentially decreased by equal difference to d2 and d3... dn; the width of the grid hollowed-out area of the mask plate along the CD direction in fig. 6 is the same as that of the grid hollowed-out area along the AB direction, and the grid hollowed-out area is sequentially decreased in an equal difference mode, so that an OLED (organic light emitting diode) organic material functional film layer with a convex surface can be manufactured by using the evaporation mask plate, and the thickness of the film layer is sequentially decreased from the middle area to the edge area. Of course, those skilled in the art will understand that the specific arrangement of the opening is not limited to the case shown in fig. 7, and all reasonable changes and substitutions without departing from the design idea of the present invention are within the protection scope of the present invention.

In yet another aspect of the present invention, the present invention provides a method of fabricating an organic electroluminescent display device. According to an embodiment of the present invention, referring to fig. 8, the method includes:

s100: an anode is formed.

According to the embodiment of the invention, the preparation method and the material of the anode are not particularly limited, and the anode can be flexibly selected by a person skilled in the art according to the actual situation. In some embodiments of the present invention, the anode can be formed by vacuum thermal evaporation. Therefore, the method is simple and convenient to operate, is easy for large-scale production, and has good anode performance and high yield. In some embodiments of the present invention, the material forming the anode may be a transparent conductive oxide, such as ITO, or a transparent conductive material such as a conductive polymer. Therefore, the light-emitting diode has higher light transmittance and is beneficial to improving the display effect.

According to an embodiment of the present invention, the anode may be directly formed on the array substrate by evaporation in this step, and the specific structure of the array substrate refers to fig. 5, and the array substrate is the same as the array substrate described above, which is not described in detail herein.

S200: an organic functional layer is formed on one side of the anode.

According to the embodiment of the invention, in the step, the organic functional layer with the convex surface which is convex towards the direction far away from the anode is formed, so that when the cathode is formed in the subsequent step, the first surface of the cathode close to the organic functional layer is matched with the surface of the organic functional layer, and the first surface of the cathode is formed into the surface with the function of converging light in the aspect of light outgoing.

Specifically, the organic functional layer satisfying the requirements can be formed by vapor deposition using a special mask, namely, the OLED material is heated by a crucible in a vacuum cavity, the pattern of an OLED organic functional layer is manufactured by utilizing an evaporation mask, the structural schematic diagram of the adopted mask is shown in figure 6, the mask comprises a middle transmission area 001 and an edge non-transmission area 002, wherein, the middle transmission area 001 is in a grid shape, the grid transmission area 001 comprises a grid hollow-out area 003 and a grid non-hollow-out area 004 at the edge of the grid hollow-out area 003, when in vapor deposition, the organic material particles can pass through the grid hollow-out area 003 to reach the vapor deposition substrate, therefore, the growth of the organic functional layer is realized, and the organic material can reach the position below the grid non-hollow-out area 004 due to the diffusion property of the material, so that the continuous organic functional layer is formed.

According to an embodiment of the present invention, referring to fig. 4A to 4C, the organic functional layer may include one of: (a) a light emitting layer; (b) the electron transport layer, the light emitting layer and the hole transport layer are sequentially stacked along the direction from the cathode to the anode; (c) the light-emitting diode comprises an electron injection layer, an electron transport layer, a light-emitting layer, a hole transport layer and a hole injection layer which are sequentially stacked along the direction from a cathode to an anode, wherein the surface, close to the cathode, of at least one of the electron injection layer, the electron transport layer, the light-emitting layer, the hole transport layer and the hole injection layer is matched with the first surface.

In the specific process of preparing the organic functional layer, the organic functional layer can be formed by evaporation layer by layer according to the direction of the anode facing the cathode, and the organic functional layer can be formed by adopting the mask plate when at least one of the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer and the hole injection layer is formed by evaporation, so that the convex surface protruding towards the direction far away from the anode is formed on the surface of the organic functional layer close to the cathode, and further the first surface of the cathode forms a corresponding convex surface, and the function of converging light rays towards the light emitting direction is achieved. For example, in the case of using the mask only for preparing the electron injection layer, the hole injection layer 10, the hole transport layer 11, the light emitting layer 12, and the electron transport layer 13 may be sequentially deposited on the array substrate on which the anode is formed by using a general mask, and then the electron injection layer 14 having a thick middle layer and thin two sides may be formed by using the above-mentioned special deposition mask, and the schematic structural diagram is shown in fig. 4C. In another embodiment, the electron transport layer 13 of the OLED display device is also formed into a shape with a thick middle layer and a thin periphery by using the mask through evaporation, and the structural schematic diagram is shown in fig. 4D, at this time, the thicknesses of the electron transport layer 13 and the electron injection layer 14 are overlapped together and are larger, and the curvature radius of the first surface 17 of the cathode can be adjusted and controlled to a larger extent by adjusting the size of the tolerance of the grid hollowed-out region in the grid-shaped transmission region 001 in the mask, which is sequentially decreased in an equal difference manner towards two sides, so that the light extraction efficiency of the OLED device can be better adjusted and controlled. Meanwhile, the hole injection layer 10, the hole transport layer 11, the light emitting layer 12, and the like can also be formed into a shape with a thick middle part and a thin periphery by using the mask through an evaporation method, which is not limited herein, and can be flexibly adjusted by a person skilled in the art as needed, and thus, redundant description is not repeated herein. S300: a cathode is formed on the side of the organic functional layer remote from the anode.

According to an embodiment of the present invention, in this step, the cathode is disposed adjacent to the first surface of the organic functional layer to converge light toward a light-emitting direction of the organic electroluminescent display device.

Specifically, in the above step, the organic functional layer having a specific shape is formed, and in this step, only the OLED cathode 15 covering the organic functional layer needs to be manufactured, and the first surface of the cathode naturally forms a shape matching the surface of the organic functional layer close to the cathode. Referring to fig. 5, it is easy to know that the thickness of the cathode 15 is uniform, the cathode 15 is bent to form an arc surface covering the organic functional layer of the OLED, and for the light emitted by the organic functional layer, the cathode 15 becomes a concave mirror, so that the light irradiated from the light-emitting layer is reflected from the OLED and has a certain gathering effect on the reflected light, thereby increasing the light-emitting efficiency of the OLED device. Preferably, the center of the arc surface of the cathode 15 is set at the point a on the lower surface of the substrate 1, and then part of the light rays irradiated onto the cathode 15 will converge on the lower surface of the substrate 1, and the structural schematic diagram is shown in fig. 6.

The inventor finds that the organic electroluminescent display device prepared by the method can reflect light irradiated from the light-emitting layer out of the bottom of the OLED and has certain gathering effect on the reflected light, so that the light-emitting efficiency of the bottom-emitting OLED device is increased, and the service life of a light-emitting material is prolonged.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims (10)

1. An organic electroluminescent display device, comprising:

a cathode;

an anode; and

an organic functional layer filled between the cathode and the anode,

wherein, the surface of the cathode close to the organic functional layer is a first surface, the part of the first surface contacting with the organic functional layer forms a second surface, the part of the second surface, which is in the orthographic projection of the anode in the light emergent direction of the organic electroluminescent display device and falls on the orthographic projection of the cathode in the light emergent direction, is set to converge light in the light emergent direction,

and the second surface is positioned at one side departing from the light-emitting direction of the organic electroluminescent display device.

2. The organic electroluminescent display device according to claim 1, wherein a portion of the orthographic projection of the second surface in the light outgoing direction falling into the orthographic projection of the anode in the light outgoing direction is a convex surface protruding away from the organic functional layer.

3. The organic electroluminescent display device according to claim 2, wherein a portion of the second surface in which an orthographic projection of the second surface in a light outgoing direction falls in an orthographic projection of the anode in the light outgoing direction is formed as a curved surface convex toward a direction away from the organic functional layer.

4. The organic electroluminescent display device according to claim 2, wherein the portion of the second surface in which the orthographic projection in the light exit direction falls in the orthographic projection of the anode in the light exit direction includes a central plane and a peripheral curved surface disposed around and contiguous with the central plane, wherein the peripheral curved surface gradually approaches the central plane in a direction away from the anode.

5. The organic electroluminescent display device according to any one of claims 1 to 4, wherein the organic functional layer comprises one of:

(a) a light emitting layer;

(b) the electron transport layer, the light emitting layer and the hole transport layer are sequentially stacked along the direction from the cathode to the anode;

(c) the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer and the hole injection layer are sequentially stacked along the direction from the cathode to the anode;

wherein a surface of at least one of the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer, and the hole injection layer near the cathode matches the first surface.

6. The organic electroluminescent display device according to claim 5, wherein the focus of the light convergence is located on the light emitting surface of the organic electroluminescent display device.

7. A display apparatus comprising the organic electroluminescent display device according to any one of claims 1 to 6.

8. The utility model provides a mask for preparing organic electroluminescent display device, a serial communication port, includes the mask main part, the mask main part is provided with a plurality of openings, follows the center of mask main part is started, is followed the central line direction of mask main part, the open area of a plurality of openings reduces gradually for form continuous organic functional layer, organic functional layer deviates from the surface of organic electroluminescent display device's light-emitting direction is for dorsad the bellied convex surface of light-emitting direction.

9. A method of making an organic electroluminescent display device, comprising:

forming an anode;

forming an organic functional layer on one side of the anode;

forming a cathode on the side of the organic functional layer away from the anode;

wherein, the surface of the cathode close to the organic functional layer is a first surface, the part of the first surface contacting with the organic functional layer forms a second surface, the part of the second surface, which is in the orthographic projection of the anode in the light emergent direction of the organic electroluminescent display device and falls on the orthographic projection of the cathode in the light emergent direction, is set to converge light in the light emergent direction,

and the second surface is positioned at one side departing from the light-emitting direction of the organic electroluminescent display device.

10. The method of claim 9, wherein the organic functional layer is formed using the reticle of claim 8.

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