Display device

Abstract

An organic EL element layer (30a), which has a second electrode (24) that is provided so as to be shared by a plurality of subpixels (P) corresponding to a plurality of first electrodes (21) on an organic EL layer (23), is provided with an auxiliary electrode (Cbn) and a plurality of differentially coated electrodes (Cp) in an upper layer and / or lower layer of the second electrode (24). The auxiliary electrode (Cbn) is provided to a bank region (Bn), which does not overlap with a light emission region (L) of the plurality of subpixels (P) in a plan view. The plurality of differentially coated electrodes (Cp) are each provided so as to overlap with at least part of a light emission region (L) of the plurality of subpixels (P) in a plan view.

Description

display device

[0001] The present invention relates to a display device.

[0002] In recent years, self-luminous organic electroluminescence (EL) display devices using organic electroluminescence (EL) elements have been attracting attention as a display device that can replace liquid crystal display devices. An organic EL display device includes, for example, a base substrate and a TFT layer on which a plurality of thin film transistors (TFTs) for driving organic EL elements are formed for each subpixel constituting a display area, and an organic EL element layer on the TFT layer. Here, the organic EL element includes, for example, a first electrode on the TFT layer, an organic EL layer on the first electrode as a light-emitting functional layer, and a second electrode (upper electrode) on the organic EL layer.

[0003] In organic EL display devices equipped with top-emission organic EL elements, a thin second electrode is preferable in terms of improving light extraction efficiency and viewing angle characteristics. However, a thin second electrode increases resistance (decreasing current efficiency), which can lead to a problem of IR drop, which prevents uniform light emission across the panel surface when the display panel is enlarged or the second electrode is made thinner. On the other hand, a thick second electrode reduces resistance, improving current efficiency but decreasing viewing angle characteristics and light extraction efficiency.

[0004] For example, Patent Document 1 proposes a top-emission organic EL display device that prevents a voltage drop in the upper electrode due to high resistance of the upper electrode and achieves uniform screen brightness. Also, Patent Document 2 proposes an active-matrix-driven organic EL display device that is suitable for top-emission light extraction and has electrodes with low resistance without suffering from degradation in characteristics.

[0005] JP 2009-94347 A JP 2007-95515 A

[0006] However, in the organic EL display device described in Patent Document 1, by forming an auxiliary electrode above or below the upper electrode by vapor deposition or sputtering, the voltage drop of the upper electrode is suppressed and the uniformity of the screen brightness is improved, but the optical characteristics such as the viewing angle characteristics, light extraction efficiency, and applied voltage margin are insufficient and there is room for improvement.

[0007] Furthermore, the organic EL display device described in Patent Document 2 has an auxiliary electrode above the second electrode, so even if the second electrode itself is thin and has high resistance, it can supply sufficient current to each pixel. As a result, the uniformity of screen brightness and light extraction efficiency are improved, but the optical characteristics such as viewing angle characteristics and applied voltage margin are insufficient and there is room for improvement.

[0008] As described above, in a top-emission organic EL display device, it is difficult to achieve both uniformity of screen brightness (IR drop) due to the film thickness of the second electrode and optical characteristics (viewing angle characteristics, light extraction efficiency, applied voltage margin, etc.).

[0009] The present invention has been made in view of the above points, and an object of the present invention is to achieve both uniformity of screen luminance and good optical characteristics in a top-emission organic EL display device.

[0010] In order to achieve the above object, the display device of the present invention is a display device comprising: a base substrate; a thin film transistor layer provided on the base substrate; a plurality of first electrodes provided on the thin film transistor layer; an edge cover in which a plurality of openings corresponding to the plurality of first electrodes are formed; a light-emitting element layer having a light-emitting function layer on the plurality of first electrodes and a portion thereof on the edge cover; and a second electrode provided on the light-emitting function layer in common to a plurality of sub-pixels corresponding to the plurality of first electrodes, wherein the light-emitting element layer comprises an auxiliary electrode and a plurality of separate color electrodes above and / or below the second electrode, the auxiliary electrode being provided in a bank region that does not overlap with the light-emitting regions of the plurality of sub-pixels in a planar view, and the plurality of separate color electrodes being each provided so as to overlap with at least a portion of the light-emitting regions of the plurality of sub-pixels in a planar view.

[0011] According to the present invention, it is possible to achieve both uniformity of screen brightness and good optical characteristics in a top-emission organic EL display device.

[0012] FIG. 1 is a plan view showing a schematic configuration of an organic EL display device according to a first embodiment of the present invention. FIG. 2 is a plan view of a display region of the organic EL display device according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view of a display region of the organic EL display device according to the first embodiment of the present invention. FIG. 4 is an equivalent circuit diagram showing a pixel circuit of the organic EL display device according to the first embodiment of the present invention. FIG. 5 is a cross-sectional view showing an organic EL layer constituting the organic EL display device according to the first embodiment of the present invention. FIG. 6 is an enlarged cross-sectional view showing an organic EL element layer constituting the organic EL display device according to the first embodiment of the present invention. FIG. 7 is a plan view showing an organic EL element layer constituting the organic EL display device according to the first embodiment of the present invention. FIG. 8 is a cross-sectional view showing an organic EL element layer constituting the organic EL display device according to the first embodiment of the present invention. FIG. 9 is a plan view showing a modified organic EL element layer (auxiliary electrodes constituting the organic EL element layer) constituting the organic EL display device according to the first embodiment of the present invention. FIG. 10 is a cross-sectional view showing a modified organic EL element layer (auxiliary electrodes constituting the organic EL element layer) constituting the organic EL display device according to the first embodiment of the present invention. FIG. 11 is an enlarged cross-sectional view showing an organic EL element layer constituting an organic EL display device according to a second embodiment of the present invention, and corresponds to FIG. 6 .

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments.

[0014] First Embodiment FIGS. 1 to 10 show a first embodiment of a display device according to the present invention. In the following embodiments, an organic EL display device including organic EL elements will be exemplified as a display device including light-emitting elements. FIG. 1 is a plan view showing a schematic configuration of an organic EL display device 50a according to this embodiment. FIG. 2 is a plan view of a display region D of the organic EL display device 50a. FIG. 3 is a cross-sectional view of the display region D of the organic EL display device 50a. FIG. 4 is an equivalent circuit diagram showing a pixel circuit C of the organic EL display device 50a. FIG. 5 is a cross-sectional view of an organic EL layer 23 constituting the organic EL display device 50a. FIG. 6 is an enlarged cross-sectional view of an organic EL element layer 30a constituting the organic EL display device 50a. FIG. 7 is a plan view of the organic EL element layer 30a constituting the organic EL display device 50a. FIG. 8 is a cross-sectional view of the organic EL element layer 30a constituting the organic EL display device 50a. FIG. 9 is a plan view showing a modified example of the organic EL element layer 30a (auxiliary electrodes Cbn constituting the organic EL element layer 30a) constituting the organic EL display device 50a. 10 is a cross-sectional view showing a modified example of the organic EL element layer 30a (auxiliary electrodes Cbn constituting the organic EL display device 50a). Note that the upper layer of the organic EL element layer 30a is omitted in FIGS. 8 and 10.

[0015] 1, the organic EL display device 50a includes, for example, a rectangular display area D for displaying an image, and a frame area F provided in a frame shape around the display area D. Note that, although the present embodiment illustrates a rectangular display area D, this rectangular shape also includes, for example, a substantially rectangular shape with arc-shaped sides, arc-shaped corners, or a shape with a notch in one of the sides.

[0016] As shown in FIG. 2 , a plurality of sub-pixels P are arranged in a matrix in the display region D. Also, as shown in FIG. 2 , the display region D includes a sub-pixel P having a red light-emitting region Lr (light-emitting region L) for displaying red, a sub-pixel P having a green light-emitting region Lg (light-emitting region L) for displaying green, and a sub-pixel P having a blue light-emitting region Lb (light-emitting region L) for displaying blue, which are arranged adjacent to each other. In the display region D, one pixel is formed by, for example, three adjacent sub-pixels P each having a red light-emitting region Lr, a green light-emitting region Lg, and a blue light-emitting region Lb. The arrangement of the sub-pixels P is not particularly limited, and examples thereof include a pentatile arrangement, a stripe arrangement, and a diamond arrangement. The following description will be given using the sub-pixels P in a diamond arrangement as an example.

[0017] 1, a terminal portion T is provided to extend in one direction (the vertical direction in FIG. 1) at one end (the right end in FIG. 1) of the frame region F. In addition, a folding portion B is provided in the frame region F between the terminal portion T and the display region D, and extends in one direction (the vertical direction in FIG. 1) and can be folded, for example, 180 degrees (in a U-shape) with the vertical direction in FIG. 1 as the folding axis.

[0018] As shown in FIG. 3, the organic EL display device 50a includes a resin substrate 10 provided as a base substrate, a TFT layer 20 provided on the resin substrate 10, an organic EL element layer 30a provided as a light-emitting element layer on the TFT layer 20, and a sealing film 35 provided on the organic EL element layer 30a.

[0019] The resin substrate 10 is made of an organic resin material such as polyimide (PI) resin.

[0020] As shown in FIG. 3, the TFT layer 20 includes a base coat film 11 provided on a resin substrate 10, a plurality of first TFTs 9a, a plurality of second TFTs 9b, and a plurality of capacitors 9c provided on the base coat film 11 for each subpixel P, and a planarization film 19 provided on each of the first TFTs 9a, each of the second TFTs 9b, and each of the capacitors 9c. 3, the TFT layer 20 includes a base coat film 11, semiconductor layers 12a and 12b, a gate insulating film 13, a first wiring layer including gate lines 14 (see FIG. 2), gate electrodes 14a and 14b, and a lower conductive layer 14c, a first interlayer insulating film 15, a second wiring layer including upper conductive layer 16, a second interlayer insulating film 17, a third wiring layer including source lines 18f (see FIG. 2), source electrodes 18a and 18c, drain electrodes 18b and 18d, and a power line 18g, and a planarization film 19, which are stacked in this order on a resin substrate 10. Also, as shown in FIGS. 2 and 4, the TFT layer 20 includes a plurality of gate lines 14 extending parallel to one another in the horizontal direction in the drawings. Also, as shown in FIGS. 2 and 4, the TFT layer 20 includes a plurality of source lines 18f extending parallel to one another in a direction intersecting (orthogonal to) the plurality of gate lines 14, i.e., in the vertical direction in the drawings. 2 and 4, the TFT layer 20 is provided with a plurality of power supply lines 18g extending parallel to one another in the vertical direction in the drawings. Each power supply line 18g is provided adjacent to a corresponding source line 18f, as shown in Fig. 2. In the TFT layer 20, a first TFT 9a, a second TFT 9b, and a capacitor 9c are provided as a pixel circuit C in each sub-pixel P, as shown in Fig. 4. The pixel circuits C are arranged in a matrix corresponding to each sub-pixel P.

[0021] The base coat film 11, the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17 may be made of, for example, silicon nitride (SiNx (x is a positive number)), silicon oxide (SiO ２The semiconductor layers 12a and 12b are each composed of a single layer or a stacked layer of an inorganic insulating film such as silicon oxynitride (SiON). The semiconductor layers 12a and 12b are composed of, for example, a low-temperature polysilicon film or an In—Ga—Zn—O-based oxide semiconductor film. The first wiring layer, the second wiring layer, and the third wiring layer are each composed of, for example, a metal single layer film of molybdenum (Mo), titanium (Ti), aluminum (Al), copper (Cu), tungsten (W), or the like, or a metal stacked layer film of Mo (upper layer) / Al (middle layer) / Mo (lower layer), Ti / Al / Ti, Al (upper layer) / Ti (lower layer), Cu / Mo, Cu / Ti, or the like.

[0022] The first TFT 9a and the second TFT 9b are p-type TFTs in which the semiconductor layers 12a and 12b are doped with impurities such as boron.

[0023] As shown in FIG. 4 , the first TFT 9a is electrically connected to the corresponding gate line 14 and source line 18f in each subpixel P. As shown in FIG. 3 , the first TFT 9a includes a semiconductor layer 12a, a gate insulating film 13, a gate electrode 14a, a first interlayer insulating film 15, a second interlayer insulating film 17, a source electrode 18a, and a drain electrode 18b, which are sequentially disposed on a base coat film 11. As shown in FIG. 3 , the semiconductor layer 12a is disposed on the base coat film 11 in an island shape and has, for example, a channel region, a source region, and a drain region. As shown in FIG. 3 , the gate insulating film 13 is disposed so as to cover the semiconductor layer 12a. As shown in FIG. 3 , the gate electrode 14a is disposed on the gate insulating film 13 so as to overlap the channel region of the semiconductor layer 12a. As shown in FIG. 3 , the first interlayer insulating film 15 and the second interlayer insulating film 17 are disposed so as to cover the gate electrode 14a. 3, the source electrode 18a and the drain electrode 18b are provided spaced apart from each other on the second interlayer insulating film 17. The source electrode 18a and the drain electrode 18b are electrically connected to the source region and the drain region of the semiconductor layer 12a, respectively, through contact holes formed in the stacked film of the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17.

[0024] As shown in FIG. 4 , the second TFT 9b is electrically connected to the corresponding first TFT 9a and power line 18g in each subpixel P. As shown in FIG. 3 , the second TFT 9b includes a semiconductor layer 12b, a gate insulating film 13, a gate electrode 14b, a first interlayer insulating film 15, a second interlayer insulating film 17, a source electrode 18c, and a drain electrode 18d, which are sequentially disposed on a base coat film 11. As shown in FIG. 3 , the semiconductor layer 12b is disposed on the base coat film 11 in an island shape and includes, for example, a channel region, a source region, and a drain region. As shown in FIG. 3 , the gate insulating film 13 is disposed so as to cover the semiconductor layer 12b. As shown in FIG. 3 , the gate electrode 14b is disposed on the gate insulating film 13 so as to overlap the channel region of the semiconductor layer 12b. As shown in FIG. 3 , the first interlayer insulating film 15 and the second interlayer insulating film 17 are sequentially disposed so as to cover the gate electrode 14b. 3, the source electrode 18c and the drain electrode 18d are provided spaced apart from each other on the second interlayer insulating film 17. The source electrode 18c and the drain electrode 18d are electrically connected to the source region and the drain region of the semiconductor layer 12b, respectively, through contact holes formed in the stacked film of the gate insulating film 13, the first interlayer insulating film 15, and the second interlayer insulating film 17.

[0025] In this embodiment, the first TFT 9a and the second TFT 9b are top-gate type TFTs, but the first TFT 9a and the second TFT 9b may be bottom-gate type TFTs.

[0026] As shown in Fig. 4, the capacitor 9c is electrically connected to the corresponding first TFT 9a and power supply line 18g in each subpixel P. Here, as shown in Fig. 3, the capacitor 9c includes a lower conductive layer 14c formed in the same layer and made of the same material as the gate electrodes 14a and 14b, a first interlayer insulating film 15 provided so as to cover the lower conductive layer 14c, and an upper conductive layer 16 provided on the first interlayer insulating film 15 so as to overlap the lower conductive layer 14c. Note that the upper conductive layer 16 is electrically connected to the power supply line 18g via a contact hole formed in a second interlayer insulating film 17, as shown in Fig. 3.

[0027] The planarization film 19 has a flat surface in the display region D, and is made of, for example, an organic resin material such as polyimide resin or acrylic resin, or a polysiloxane-based SOG (spin on glass) material.

[0028] As shown in FIGS. 3 and 6, the organic EL element layer 30a includes a plurality of organic EL elements 25 as a plurality of light-emitting elements arranged in a matrix corresponding to a plurality of sub-pixels P.

[0029] 3 and 6, the organic EL element 25 includes a plurality of first electrodes 21 provided in order on the planarization film 19, a plurality of organic EL layers 23 as a plurality of light-emitting functional layers provided on the first electrodes 21 in each sub-pixel P, and a second electrode 24 provided on the organic EL layer 23 in common to the plurality of sub-pixels P. In addition, the organic EL element 25 is covered with a sealing film 35 as shown in FIG.

[0030] 3 and 6, the first electrodes 21 are provided in a matrix on the planarization film 19 so as to correspond to the plurality of sub-pixels P. As shown in FIG. 3, each first electrode 21 is electrically connected to the drain electrode 18d (or source electrode 18c) of each second TFT 9b via a contact hole formed in the planarization film 19. The first electrodes 21 have the function of injecting holes into the organic EL layer 23. In order to improve the efficiency of hole injection into the organic EL layer 23, it is more preferable that the first electrodes 21 be made of a material with a large work function. Here, examples of materials constituting the first electrode 21 include metal materials such as silver (Ag), aluminum (Al), vanadium (V), cobalt (Co), nickel (Ni), tungsten (W), gold (Au), titanium (Ti), ruthenium (Ru), manganese (Mn), indium (In), ytterbium (Yb), lithium fluoride (LiF), platinum (Pt), palladium (Pd), molybdenum (Mo), iridium (Ir), and tin (Sn). Examples of materials constituting the first electrode 21 include astatine (At) / astatine oxide (AtO ２) or an alloy thereof. Furthermore, the material constituting the first electrode 21 may be, for example, a conductive oxide such as tin oxide (SnO), zinc oxide (ZnO), indium tin oxide (ITO), or indium zinc oxide (IZO). The first electrode 21 may also be formed by stacking multiple layers made of the above materials. Examples of compound materials with a large work function include indium tin oxide (ITO) and indium zinc oxide (IZO). In the following description, the first electrode 21 is described as an anode.

[0031] The peripheral edge of the first electrode 21 is covered by an edge cover 22 provided in a lattice pattern and shared by multiple subpixels P. Examples of materials for the edge cover 22 include positive-type photosensitive resin materials such as polyimide resin, acrylic resin, polysiloxane resin, and novolac resin, as well as polysiloxane-based SOG materials. As shown in FIG. 3 (also see FIGS. 8 and 10 ), a portion of the surface of the edge cover 22 protrudes upward in the drawing to form island-shaped pixel photospacers (columnar spacers) PS. As shown in FIG. 3 (also see FIGS. 8 and 10 ), the lattice-shaped edge cover 22 has multiple openings 22 a formed therein corresponding to the multiple first electrodes 21. In other words, the multiple openings 22 a overlap the multiple first electrodes 21 in a planar view.

[0032] 3 and 6 (see also FIGS. 8 and 10 ), the organic EL layer 23 is disposed on each first electrode 21, and is provided in a matrix so as to correspond to a plurality of sub-pixels P. Here, each organic EL layer 23 includes a hole injection layer 1, a hole transport layer 2, a light-emitting layer 3, an electron transport layer 4, and an electron injection layer 5, which are provided in this order on the first electrode 21, as shown in FIG.

[0033] The hole injection layer 1 is also called an anode buffer layer, and has the function of bringing the energy levels of the first electrode 21 and the organic EL layer 23 closer to each other, thereby improving the efficiency of hole injection from the first electrode 21 to the organic EL layer 23. Examples of materials constituting the hole injection layer 1 include triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, phenylenediamine derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, and stilbene derivatives.

[0034] The hole transport layer 2 has a function of improving the efficiency of transporting holes from the first electrode 21 to the organic EL layer 23. Examples of materials constituting the hole transport layer 2 include porphyrin derivatives, aromatic tertiary amine compounds, styrylamine derivatives, polyvinylcarbazole, poly-p-phenylenevinylene, polysilane, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amine-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, hydrogenated amorphous silicon, hydrogenated amorphous silicon carbide, zinc sulfide, and zinc selenide.

[0035] The light-emitting layer 3 is a region into which holes and electrons are injected from the first electrode 21 and the second electrode 24, respectively, and where the holes and electrons recombine when a voltage is applied between the first electrode 21 and the second electrode 24. The light-emitting layer 3 is made of a material with high luminous efficiency. Examples of materials that can be used for the light-emitting layer 3 include metal oxinoid compounds (8-hydroxyquinoline metal complexes), naphthalene derivatives, anthracene derivatives, diphenylethylene derivatives, vinylacetone derivatives, triphenylamine derivatives, butadiene derivatives, coumarin derivatives, benzoxazole derivatives, oxadiazole derivatives, oxazole derivatives, benzimidazole derivatives, thiadiazole derivatives, benzthiazole derivatives, styryl derivatives, styrylamine derivatives, bisstyrylbenzene derivatives, trisstyrylbenzene derivatives, perylene derivatives, perinone derivatives, aminopyrene derivatives, pyridine derivatives, rhodamine derivatives, aquidin derivatives, phenoxazone, quinacridone derivatives, rubrene, poly-p-phenylenevinylene, and polysilane.

[0036] The electron transport layer 4 has a function of efficiently transferring electrons to the light-emitting layer 3. Examples of materials constituting the electron transport layer 4 include organic compounds such as oxadiazole derivatives, triazole derivatives, benzoquinone derivatives, naphthoquinone derivatives, anthraquinone derivatives, tetracyanoanthraquinodimethane derivatives, diphenoquinone derivatives, fluorenone derivatives, silole derivatives, and metal oxinoid compounds.

[0037] The electron injection layer 5 has a function of bringing the energy levels of the second electrode 24 and the organic EL layer 23 closer to each other and improving the efficiency of electron injection from the second electrode 24 to the organic EL layer 23, and this function can reduce the driving voltage of the organic EL element 25. The electron injection layer 5 is also called a cathode buffer layer. Here, examples of materials constituting the electron injection layer 5 include lithium fluoride (LiF), magnesium fluoride (MgF ２ ), calcium fluoride (CaF ２ ), strontium fluoride (SrF ２ ), barium fluoride (BaF ２inorganic alkali compounds such as aluminum oxide (Al ２ O ３ ), strontium oxide (SrO), etc.

[0038] As shown in FIGS. 3 and 6 (also see FIGS. 8 and 10 ), the second electrode 24 is provided to cover each organic EL layer 23 and the edge cover 22. The second electrode 24 has a function of injecting electrons into the organic EL layer 23. To improve the efficiency of electron injection into the organic EL layer 23, the second electrode 24 is preferably made of a material with a small work function. Examples of materials that can be used for the second electrode 24 include silver (Ag), aluminum (Al), vanadium (V), cobalt (Co), nickel (Ni), tungsten (W), gold (Au), calcium (Ca), titanium (Ti), yttrium (Y), sodium (Na), ruthenium (Ru), manganese (Mn), indium (In), magnesium (Mg), lithium (Li), ytterbium (Yb), and lithium fluoride (LiF). The second electrode 24 may be made of, for example, magnesium (Mg) / copper (Cu), magnesium (Mg) / silver (Ag), sodium (Na) / potassium (K), or astatine (At) / astatine oxide (AtO ２The second electrode 24 may be formed of an alloy such as lithium (Li) / aluminum (Al), lithium (Li) / calcium (Ca) / aluminum (Al), or lithium fluoride (LiF) / calcium (Ca) / aluminum (Al). The second electrode 24 may be formed of a conductive oxide such as tin oxide (SnO), zinc oxide (ZnO), indium tin oxide (ITO), or indium zinc oxide (IZO). The second electrode 24 may be formed by stacking multiple layers made of the above materials. Examples of materials with a low work function include magnesium (Mg), lithium (Li), lithium fluoride (LiF), magnesium (Mg) / copper (Cu), magnesium (Mg) / silver (Ag), sodium (Na) / potassium (K), lithium (Li) / aluminum (Al), lithium (Li) / calcium (Ca) / aluminum (Al), and lithium fluoride (LiF) / calcium (Ca) / aluminum (Al). In the following, the second electrode 24 is also referred to as the “cathode 24” and will be described as the cathode. The thickness of the cathode 24 is preferably as thin as possible in terms of the resistance of the subpixel P and the applied voltage margin, but is set to, for example, 10 nm or more from the viewpoint of suppressing lighting defects due to high resistance.

[0039] 6 to 10, in the organic EL display device 50a of this embodiment, the auxiliary electrodes Cbn and the separate color electrodes Cp (Cpr, Cpg, Cpb) are provided on the cathode 24. The organic EL element layer 30a includes the auxiliary electrodes Cbn and the separate color electrodes Cp, which are formed in the same layer as the upper layer of the cathode 24.

[0040] 6 to 10, the auxiliary electrode Cbn is provided in a bank region Bn, which is a non-light-emitting region that does not overlap in a planar view with the light-emitting regions L consisting of the red light-emitting regions Lr, green light-emitting regions Lg, and blue light-emitting regions Lb of the plurality of sub-pixels P. Specifically, as shown in FIGS. 7 to 10, the auxiliary electrode Cbn is provided between adjacent light-emitting regions L in a planar view.

[0041] 6, 8, and 10, the auxiliary electrode Cbn is laminated on the cathode 24 in the bank region Bn and has the function of thickening the cathode. In other words, the auxiliary electrode Cbn can be said to be an auxiliary cathode that adjusts (thickens) the film thickness of the cathode 24 in the bank region Bn to assist its function. Hereinafter, the auxiliary electrode Cbn will also be referred to as "auxiliary cathode Cbn" and will be described as a cathode.

[0042] As described above, conventional organic EL display devices have a problem of IR drop, which causes greater variations in brightness and current distribution within the display panel surface as the distance from the current input terminal (terminal portion T) increases due to the thin, high-resistance second electrode (cathode). This prevents uniform light emission across the panel surface. In contrast, the organic EL display device 50a of this embodiment has a stacked film structure of the cathode 24 and the auxiliary cathode Cbn in the bank region Bn, thereby thickening the cathode and improving the uniformity of screen brightness. Note that if the cathode 24 itself, which is common to the organic EL layer 23, is thickened in order to reduce the IR drop, the optical characteristics of the organic EL element 25, such as the viewing angle characteristics and light extraction efficiency, may be degraded.

[0043] The auxiliary cathode Cbn can be made of the same material as the cathode 24. Among these, the auxiliary cathode Cbn is preferably made of copper (Cu), aluminum (Al), alloys containing these materials, or conductive polymer materials, which are low-cost and have excellent electrical conductivity. The auxiliary cathode Cbn may also be formed by stacking multiple layers made of the above materials. Using the above materials as the auxiliary cathode Cbn hardly affects the light extraction efficiency of the light-emitting region (the RGB pixel region Prgb described below) where the subpixels P are arranged, thereby enabling cost reduction of the cathode material.

[0044] The auxiliary cathodes Cbn may be formed in a plurality of island shapes, as shown in FIG. 7 . As shown in FIG. 8 , the island-shaped auxiliary cathodes Cbn are provided so as to cover the pixel photospacers PS (see also FIG. 3 ) that are provided in an island shape on a portion of the surface of the edge cover 22. By forming an auxiliary cathode on each pixel photospacer PS along its shape, the auxiliary cathode becomes a spacer-type island-shaped auxiliary electrode Cbn that protrudes toward the sealing film 35 (see FIG. 3 ) in cross-sectional view. Alternatively, the auxiliary cathodes Cbn may be formed in a lattice shape, as shown in FIG. 9 . As shown in FIG. 8 , the lattice-shaped auxiliary cathodes Cbn are provided so as to cover both the island-shaped pixel photospacers PS and the edge cover 22 that is provided in a lattice shape. By forming a cathode on the edge cover 22 and the pixel photospacers PS along their shapes, the auxiliary cathode becomes a cross-connected lattice-shaped auxiliary electrode Cbn in which a portion of the surface (the portion directly above the pixel photospacer PS) protrudes toward the sealing film 35 in cross-sectional view. Among the auxiliary cathodes Cbn, the spacer-type island-shaped auxiliary cathodes Cbn are preferred because they are easy to manufacture. The planar shape of the spacer-type island-shaped auxiliary cathodes Cbn is not particularly limited, and examples thereof include a circular, elliptical, and rectangular shape.

[0045] The film thickness of the auxiliary cathode Cbn may be appropriately determined depending on the film thicknesses of the organic EL layer 23, the cathode 24, the separate color electrode Cp, etc., the panel area, the resistance of the organic EL layer 23, etc., and is not particularly limited, but is, for example, about 1 nm to 100 nm.

[0046] The color-coded electrodes Cp include at least one of an (R) red-color-coded electrode Cpr, a (G) green-color-coded electrode Cpg, and a (B) blue-color-coded electrode Cpb. The organic EL element layer 30a may include at least one of the red-color-coded electrode Cpr, the green-color-coded electrode Cpg, and the blue-color-coded electrode Cpb as the color-coded electrodes Cp.

[0047] As shown in FIGS. 6 to 10 , the color-separated electrodes Cp are provided in regions Prgb (hereinafter also referred to as "RGB pixel regions") that overlap in plan view with light-emitting regions L consisting of red light-emitting regions Lr, green light-emitting regions Lg, and blue light-emitting regions Lb of multiple sub-pixels P. The color-separated electrodes Cp are provided in a matrix pattern to correspond to the multiple sub-pixels P. Specifically, as shown in FIGS. 7 to 10 , the red color-separated electrode Cpr is provided so as to overlap with the red light-emitting region Lr in plan view. The green color-separated electrode Cpg is provided so as to overlap with the green light-emitting region Lg in plan view. The blue color-separated electrode Cpb is provided so as to overlap with the blue light-emitting region Lb in plan view. 7 and 9, the RGB color-coated electrodes Cpr, Cpg, and Cpb are formed along the shapes of the RGB color-light-emitting regions Lr, Lg, and Lb (the corresponding organic EL layers 23) so as to overlap the entire RGB color-light-emitting regions Lr, Lg, and Lb in a planar view. Note that the RGB color-coated electrodes Cpr, Cpg, and Cpb may be provided so as to overlap at least a portion of the RGB color-light-emitting regions Lr, Lg, and Lb in a planar view, as long as the effects of the present invention are not affected.

[0048] 6, 8, and 10, the RGB color-separated electrodes Cpr, Cpg, and Cpb are stacked on the cathodes 24 that overlap the RGB color light-emitting regions Lr, Lg, and Lb in a planar view in the RGB pixel region Prgb, thereby thickening the cathodes. In other words, the color-separated electrodes Cp can be considered auxiliary cathodes that are colored separately for each RGB color and adjust (thicken) the film thicknesses of the cathodes 24 that correspond to the RGB color light-emitting regions Lr, Lg, and Lb to assist their functions. Hereinafter, the color-separated electrodes Cp will also be referred to as "color-separated cathodes Cp" and will be described as cathodes.

[0049] In conventional organic EL display devices, a method of adjusting the film thickness of the organic EL layer is generally employed to improve the viewing angle characteristics. In contrast, in the organic EL display device 50a of the present embodiment, the cathode 24 in the RGB pixel region Prgb is stacked with one of the red-colored cathode Cpr, the green-colored cathode Cpg, and the blue-colored cathode Cpb, thereby thickening the cathode directly above each of the RGB light-emitting regions Lr, Lg, and Lb (the organic EL layer 23 that constitutes them) for each color, thereby improving the viewing angle characteristics (viewing angle and oblique luminance / chromaticity deviation). In addition, the light extraction efficiency due to differences in the light transmittance of each RGB color can be adjusted for each color.

[0050] The separate-colored cathode Cp can be made of the same material as the cathode 24. Among these, silver (Ag), magnesium (Mg), an alloy containing these (magnesium (Mg) / silver (Ag)), etc. are preferred as materials for the separate-colored cathode Cp. The separate-colored cathode Cp may also be formed by stacking multiple layers made of the above materials.

[0051] 8 and 10 , the separate-colored cathode Cp is provided on the cathode 24 in a region that does not overlap with the lattice-shaped edge cover 22 in plan view. Specifically, the separate-colored cathode Cp is provided so as to cover the opening 22a formed in the lattice-shaped edge cover 22. In other words, the separate-colored cathode Cp overlaps with the opening 22a in plan view. The cathode 24 in the opening 22a is recessed toward the TFT layer 20 (the side opposite the sealing film 35) by the thickness of the edge cover 22. By forming the cathode so as to fill this recess, the separate-colored cathode Cp having the desired thickness is obtained.

[0052] The film thickness of the color-separated cathode Cp may be appropriately determined depending on the film thicknesses of the organic EL layers 23, cathodes 24, auxiliary cathodes Cbn, etc. of each of the RGB colors, the resistance of the organic EL layers 23, the required optical characteristics, etc., and is not particularly limited, but is, for example, about 1 nm to 20 nm. The color-separated cathodes Cpr, Cpg, and Cpb of each of the RGB colors may have the same film thickness or different film thicknesses. That is, the film thicknesses of the color-separated cathodes Cpr, Cpg, and Cpb of each of the RGB colors may be changed for each color.

[0053] The auxiliary cathodes Cbn and the separate-colored cathodes Cp may be made of the same or different materials, and may have the same or different film thicknesses.

[0054] 3, the sealing film 35 includes a first sealing inorganic insulating film 32 provided so as to cover the cathode 24, the auxiliary cathode Cbn, and the separate color cathode Cp, a sealing organic film 33 provided on the first sealing inorganic insulating film 32, and a second sealing inorganic insulating film 34 provided so as to cover the sealing organic film 33, and has a function of protecting the organic EL layer 23 from moisture, oxygen, etc. Here, the first sealing inorganic insulating film 32 and the second sealing inorganic insulating film 34 are made of, for example, silicon oxide (SiO ２ ) and aluminum oxide (Al ２ O ３ ), trisilicon tetranitride (Si ３ N ４ The sealing organic film 33 is made of an inorganic material such as silicon nitride (SiNx (x is a positive number)) or silicon carbonitride (SiCN). The sealing organic film 33 is made of an organic material such as acrylic resin, polyurea resin, parylene resin, polyimide resin, or polyamide resin.

[0055] The organic EL display device 50a described above is configured such that, in each subpixel P, a gate signal is input to the first TFT 9a via the gate line 14 to turn the first TFT 9a on, a data signal is written to the gate electrode 14b and capacitor 9c of the second TFT 9b via the source line 18f, and a current from the power supply line 18g corresponding to the gate voltage of the second TFT 9b is supplied to the organic EL layer 23, causing the light-emitting layer 3 of the organic EL layer 23 to emit light, thereby displaying an image. In the organic EL display device 50a, even if the first TFT 9a is turned off, the gate voltage of the second TFT 9b is held by the capacitor 9c, so that light emission by the light-emitting layer 3 is maintained until a gate signal for the next frame is input.

[0056] Next, a method for manufacturing the organic EL display device 50a of this embodiment will be described. The method for manufacturing the organic EL display device 50a includes a TFT layer forming step and an organic EL element layer forming step.

[0057] <TFT layer formation process> For example, a base coat film 11, a first TFT 9 a, a second TFT 9 b, a capacitor 9 c, a planarization film 19, etc. are formed on the surface of a resin substrate 10 formed on a glass substrate using, for example, a well-known method, to form a TFT layer 20.

[0058] <Organic EL element layer forming process> A first electrode 21 (anode), an edge cover 22, an organic EL layer 23 (hole injection layer 1, hole transport layer 2, light-emitting layer 3, electron transport layer 4, electron injection layer 5), and a cathode 24 (material: for example, an Mg / Ag alloy) are formed by a well-known method on the planarization film 19 of the TFT layer 20 formed in the TFT layer forming process, thereby forming an organic EL element 25.

[0059] In the manufacturing method of the organic EL display device 50a of this embodiment, a substrate surface on which the cathode 24 has been formed is coated with, for example, Cu, Al, an alloy containing these, or a conductive polymer material, etc., on the cathode 24 in the bank region Bn, using a well-known method such as vacuum deposition, printing, or transfer, to form an auxiliary cathode Cbn.

[0060] Before, during, or after forming the auxiliary cathode Cbn, a material similar to that of the cathode 24 is laminated on the surface of the substrate on which the cathode 24 is formed, directly above the organic EL layer 23 that constitutes the RGB light-emitting regions Lr, Lg, and Lb, using a method similar to that for forming the auxiliary cathode Cbn, to form a divided cathode Cp including at least one of a red divided cathode Cpr, a green divided cathode Cpg, and a blue divided cathode Cpb. The order in which the auxiliary cathode Cbn and the divided cathode Cp are formed is not particularly limited, and either one may be formed first if the constituent materials are different, or they may be formed simultaneously if the constituent materials are the same.

[0061] In this manner, an organic EL element layer 30 a is formed, which includes the organic EL element 25 and the auxiliary cathode Cbn and separate color cathode Cp formed on the cathode 24 that constitutes the organic EL element 25 .

[0062] <Sealing Film Forming Process> The manufacturing method of the organic EL display device 50a may include a sealing film forming process. First, an inorganic insulating film such as a silicon nitride film, a silicon oxide film, or a silicon oxynitride film is formed by plasma CVD using a CMM as a deposition mask on the substrate surface on which the organic EL element layer 30a is formed, covering each organic EL element 25, the auxiliary cathodes Cbn, and the color-separated cathodes Cp, to form a first sealing inorganic insulating film 32. Next, an organic resin material such as an acrylic resin is deposited on the first sealing inorganic insulating film 32 by, for example, an inkjet method to form a sealing organic film 33. Then, an inorganic insulating film such as a silicon nitride film, a silicon oxide film, or a silicon oxynitride film is formed by plasma CVD using the CMM as a deposition mask to cover the sealing organic film 33, thereby forming a second sealing inorganic insulating film 34, thereby forming a sealing film 35. Through the above process, the sealing film 35 can be formed in the display region D, in which the first sealing inorganic insulating film 32, the sealing organic film 33, and the second sealing inorganic insulating film 34 are stacked in this order.

[0063] Finally, a protective sheet (not shown) is attached to the surface of the substrate, and then laser light is irradiated from the glass substrate side of the resin substrate 10 to peel the glass substrate from the underside of the resin substrate 10, and a protective sheet (not shown) is attached to the underside of the resin substrate 10 from which the glass substrate has been peeled. In this manner, the organic EL display device 50a can be manufactured.

[0064] <Effects> As described above, the organic EL display device 50a of this embodiment can provide the following effects.

[0065] The organic EL display device 50a includes an organic EL element layer 30a having top-emission organic EL elements 25, each of which is formed by sequentially stacking a first electrode 21 (anode), a plurality of organic EL layers 23 corresponding to each subpixel P, and a common cathode 24. An auxiliary cathode Cbn is provided on the cathode 24 in a bank region Bn that does not overlap the light-emitting region L of each subpixel P in a planar view. By stacking the auxiliary cathode Cbn on the cathode 24, the cathode in the bank region Bn is thickened. This allows sufficient current to be supplied to each subpixel P even when the cathode 24 in the RGB pixel region Prgb of the light-emitting region is thin and has high resistance. Therefore, uniform light emission can be achieved within the panel surface even when the display panel is enlarged or the cathode 24 is thinned. In other words, the uniformity of screen brightness (IR drop) can be improved. Since the auxiliary cathode Cbn is formed in the bank region Bn, it is unlikely to affect the optical characteristics of the organic EL element 25, such as the viewing angle characteristics, light extraction efficiency, and current efficiency.

[0066] Furthermore, in the organic EL display device 50a, a color-coded cathode Cp including at least one of a red-colored cathode Cpr, a green-colored cathode Cpg, and a blue-colored cathode Cpb is provided on the cathode 24 in the RGB pixel region Prgb that overlaps with the light-emitting region L of each subpixel P in a planar view. The RGB color-coded cathodes Cpr, Cpg, and Cpb are stacked on the cathode 24 directly above the organic EL layer 23 corresponding to each of the RGB light-emitting regions Lr, Lg, and Lb. By stacking the RGB color-coded cathodes Cpr, Cpg, and Cpb, which have different film thicknesses for each color, on the cathode 24, it is possible to adjust the film thicknesses of the cathodes corresponding to the RGB light-emitting regions Lr, Lg, and Lb, and as a result, it is possible to individually improve the optical characteristics (light extraction efficiency, viewing angle characteristics, etc.) of each RGB color.

[0067] Therefore, in the top-emission organic EL display device 50a, by having both the auxiliary cathodes Cbn and the separate-color cathodes Cp, it is possible to achieve both uniformity in screen luminance and good optical characteristics.

[0068] Second Embodiment Next, a second embodiment of the present invention will be described with reference to Figure 11. Figure 11 is an enlarged cross-sectional view showing an organic EL element layer 30b constituting an organic EL display device 50b of this embodiment, and is a view corresponding to Figure 6. The overall configuration of the organic EL display device 50b is the same as that of the first embodiment described above, except for the configuration of the organic EL element layer 30b, so a detailed description will be omitted here. Furthermore, components similar to those of the first embodiment will be assigned the same reference numerals and their description will be omitted.

[0069] 11 , in the organic EL display device 50b, the positions of the auxiliary cathodes Cbn and the separate-color cathodes Cp stacked as the organic EL element layer 30b are different from the positions of the layers in the organic EL element layer 30a constituting the organic EL display device 50a. Specifically, the auxiliary cathodes Cbn and the separate-color cathodes Cp are provided above the cathodes 24 in the organic EL element layer 30a, whereas they are provided below the cathodes 24 in the organic EL element layer 30b.

[0070] The auxiliary cathode Cbn is provided on the planarizing film 19 that constitutes the TFT layer 20 in the bank region Bn.

[0071] The separate color cathodes Cp (a separate red color cathode Cpr, a separate green color cathode Cpg, and a separate blue color cathode Cpb) are provided on the organic EL layers 23 constituting the RGB light-emitting regions Lr, Lg, and Lb in the RGB pixel region Prgb. That is, the separate color cathodes Cp are interposed between the organic EL layers 23 and the cathode 24. Specifically, the separate RGB color cathodes Cpr, Cpg, and Cpb are provided on the organic EL layers 23 corresponding to the RGB light-emitting regions Lr, Lg, and Lb, respectively.

[0072] All of the matters described in the first embodiment above are applicable except for the positions of the auxiliary cathodes Cbn and the separate color cathodes Cp in the organic EL element layer 30b.

[0073] The organic EL display device 50b can be obtained by changing the order of forming the upper layers of the organic EL layer 23 in the organic EL element layer forming process of the organic EL display device 50a described above. Specifically, auxiliary cathodes Cbn and separate colored cathodes Cp are formed on the substrate surface on which the organic EL layer 23 is formed. Subsequently, cathodes 24 are formed on the substrate surface on which the auxiliary cathodes Cbn and separate colored cathodes Cp are formed.

[0074] <Effects> According to the organic EL display device 50b described above, the same effects as those of the organic EL display device 50a can be obtained.

[0075] In the above-described embodiments, an organic EL element layer in which an auxiliary electrode and a separate-color electrode are provided above or below the second electrode has been exemplified, but the organic EL element layer may have an auxiliary electrode and a separate-color electrode provided both above and below the second electrode. From the viewpoint of simplifying the manufacturing process, an organic EL element layer in which an auxiliary electrode and a separate-color electrode are provided either above or below the second electrode is preferred.

[0076] In each of the above embodiments, an organic EL layer having a five-layer stacked structure of a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer has been exemplified. However, the organic EL layer may have a three-layer stacked structure of, for example, a hole injection layer / hole transport layer, a light-emitting layer, and an electron transport layer / electron injection layer.

[0077] In addition, in each of the above embodiments, an organic EL display device in which the first electrode is an anode and the second electrode is a cathode is exemplified. However, the present invention can also be applied to an organic EL display device in which the stacked structure of the organic EL layer is reversed, and the first electrode is a cathode and the second electrode is an anode.

[0078] In each of the above embodiments, an organic EL display device is exemplified in which the electrode of the TFT connected to the first electrode is used as the drain electrode, but the present invention can also be applied to an organic EL display device in which the electrode of the TFT connected to the first electrode is called the source electrode.

[0079] In the above embodiments, an organic EL display device is used as the display device, but the present invention can also be applied to display devices such as an active matrix driving liquid crystal display device.

[0080] In the above embodiments, an organic EL display device has been described as an example of a display device, but the present invention is not limited to organic EL display devices and can be applied to any flexible display device. For example, the present invention can be applied to a flexible display device including a quantum-dot light emitting diode (QLED), which is a light emitting element using a quantum dot-containing layer.

[0081] The present disclosure will be described below based on examples. Note that the present disclosure is not limited to the following examples, and the following examples can be modified or changed based on the spirit of the present disclosure, and such modifications are not excluded from the scope of the present disclosure.

[0082] (Method for manufacturing organic EL display device) According to the method for manufacturing the organic EL display device of the first embodiment described above, in the organic EL element layer formation step, color-coded cathodes (R: red / G: green / B: blue) were formed to have the film thicknesses shown in the table below, and organic EL display devices of each example were manufactured. Note that in the organic EL display device of the comparative example (base), color-coded cathodes were not formed.

[0083] (Evaluation of Organic EL Display Device) The organic EL display devices of the examples and comparative examples were evaluated for their viewing angle characteristics, ie, oblique chromaticity deviation and oblique luminance. The results are shown in Tables 1 and 2.

[0084] (1) Evaluation of chromaticity shift of white at a 45° angle from the front Using the following measurement device and measurement conditions, the chromaticity (u', v') of W (white), R (red), G (green), and B (blue) was measured at 0° from the front and at a 45° angle, and the chromaticity shift of white at a 45° angle from the front was evaluated by calculating the oblique chromaticity shift (Δu'v') according to the following calculation method. (Measurement device) Spectroradiometer (SR-UL2, manufactured by Topcon Technohouse Corporation) (Measurement conditions) - Measurement environment: Room temperature (23-25°C), low humidity environment in a clean room (CR) - Measurement location: Center of the display panel (display area of ​​the organic EL display device) - Measurement item: Chromaticity (u', v') of W, R, G, and B at 0° from the front and at a 45° angle (Calculation method of oblique chromaticity shift (Δu'v')) [Equation 1] Δu'v' = SQRT[(u' 斜め -u' 正面 )２ +(v' 斜め -v' 正面 ) ２ ]

[0085]

[0086] From the results in Table 1, it was confirmed that, compared to Comparative Example 1 (the reference), Example 1, in which the film thickness of the second cathode was reduced by 5 nm, while the green and blue cathodes were made 5 mm thick by stacking a separately painted green cathode and a separately painted blue cathode, thereby making only the red cathode 5 nm thinner, reduced the chromaticity shift of white at a 45° oblique angle by about 30%. Furthermore, compared to Comparative Example 1, Example 2, in which the film thickness of the second cathode was reduced by 5 nm, while the blue cathode alone was made 5 mm thick by stacking a separately painted blue cathode, thereby making the red and green cathodes 5 nm thinner, reduced the chromaticity shift of white at a 45° oblique angle by about 60%. Furthermore, compared to Comparative Example 1, Example 3, in which the film thickness of the second cathode was reduced by 7 nm, while the blue cathode alone was made 7 mm thick by stacking a separately painted blue cathode, thereby making the red and green cathodes 7 nm thinner, reduced the chromaticity shift of white at a 45° oblique angle by about 80%.

[0087] (2) Evaluation of white luminance at a 45° angle from the front Using the following measuring device and conditions, the luminance of W (white), R (red), G (green), and B (blue) at a 0° angle from the front and at a 45° angle (L: Luminance [cd / m 2 ]) and calculate the diagonal luminance deviation (L 斜め / L 正面 ) was calculated to evaluate the luminance of white light at a 45° angle from the front. (Measurement equipment) Spectroradiometer (SR-UL2, manufactured by Topcon Technohouse Corporation) (Measurement conditions) - Measurement environment: Room temperature (23-25°C), low humidity environment in a clean room (CR) - Measurement location: Center of the display panel (display area of ​​organic EL display device) - Measurement items: Each luminance of W, R, G and B (L: Luminance [cd / m 2 ]) (Diagonal luminance deviation (L 斜め / L 正面 ) Calculation method) [Equation 2] Normalized Luminance = L 斜め / L正面

[0088]

[0089] From the results in Table 2, it was confirmed that Example 1 had an approximately 8% improvement in the luminance of white light at a 45° angle compared to Comparative Example 1. Furthermore, it was confirmed that Examples 2 and 3 had an approximately 20 to 30% improvement in the luminance of white light at a 45° angle compared to Comparative Example 1.

[0090] (Summary) From these results, it was found that when the total thickness of the laminated film in which RGB color-coded cathodes appropriate for each color were laminated on the second cathode was reduced from 20 nm (Comparative Example 1), for example, by thinning only the red (Example 1) or by thinning both the red and green (Examples 2 and 3), the viewing angle characteristics of white (oblique chromaticity shift, oblique luminance) were significantly improved. The mechanism by which the viewing angle characteristics were improved is thought to be that by thinning the film thickness of the cathode directly above the organic EL layer 23 that constitutes the RGB color light-emitting regions Lr, Lg, and Lb, the monochromatic cavity is weakened and the viewing angle characteristics of white are improved.

[0091] As described above, the present invention is useful for flexible display devices.

[0092] Bn: Bank region Cbn: Auxiliary cathode (auxiliary electrode) Cp: Differently colored cathode (differently colored electrode) Cpr: Red-colored cathode (differently colored electrode) Cpg: Green-colored cathode (differently colored electrode) Cpb: Blue-colored cathode (differently colored electrode) L: Light-emitting region Lr: Red-light-emitting region Lg: Green-light-emitting region Lb: Blue-light-emitting region P: Subpixel Prgb: Region overlapping with the light-emitting region in plan view (RGB pixel region) PS: Pixel photospacer 10: Resin substrate (base substrate) 20: TFT layer (thin film transistor layer) 21: First electrode 22: Edge cover 22a: Opening 23: Organic EL layer (light-emitting functional layer) 24: Second cathode (second electrode) 25: Organic EL element (organic electroluminescence element, light-emitting element) 30a, 30b: Organic EL element layer (light-emitting element layer) 35: Sealing film 50a, 50b organic EL display device

Claims

1. A display device comprising: a base substrate; a thin film transistor layer provided on the base substrate; a plurality of first electrodes provided on the thin film transistor layer; an edge cover having a plurality of openings formed corresponding to the plurality of first electrodes; a light-emitting element layer having a light-emitting functional layer on the plurality of first electrodes and a portion thereof provided on the edge cover; and a second electrode provided on the light-emitting functional layer in common to a plurality of sub-pixels corresponding to the plurality of first electrodes, wherein the light-emitting element layer has an auxiliary electrode and a plurality of color-separated electrodes above and / or below the second electrode, the auxiliary electrode being provided in a bank region that does not overlap with the light-emitting regions of the plurality of sub-pixels in a planar view, and the plurality of color-separated electrodes being each provided so as to overlap with at least a portion of the light-emitting regions of the plurality of sub-pixels in a planar view.

2. The display device according to claim 1, wherein the auxiliary electrode and the plurality of separate color electrodes are formed in the same layer.

3. The display device according to claim 1 or 2, wherein the auxiliary electrodes are formed in a plurality of islands in a plan view.

4. The display device according to claim 1 or 2, wherein the auxiliary electrodes are formed in a lattice shape in a plan view.

5. A display device according to any one of claims 1 to 4, wherein the auxiliary electrode is made of copper, aluminum, an alloy containing these, or a polymeric material having electrical conductivity.

6. The display device according to any one of claims 1 to 5, wherein the plurality of color-separated electrodes are formed along the shape of the light-emitting regions of the plurality of sub-pixels so as to overlap the entire light-emitting regions of the plurality of sub-pixels in a plan view.

7. The display device according to any one of claims 1 to 6, wherein the plurality of color-separate electrodes are formed from the same material as the second electrode.

8. A display device according to claim 7, wherein the plurality of color-separated electrodes are formed from magnesium, silver or an alloy containing these which constitutes the second electrode.

9. A display device according to any one of claims 1 to 8, characterized in that the auxiliary electrode and the plurality of color-separated electrodes are provided on the second electrode, and the plurality of color-separated electrodes include a plurality of green-separated electrodes and a plurality of blue-separated electrodes.

10. A display device according to any one of claims 1 to 8, characterized in that the auxiliary electrode and the plurality of color-separated electrodes are provided on the second electrode, and the plurality of color-separated electrodes include a plurality of blue-color-separated electrodes.

11. A display device according to any one of claims 1 to 8, characterized in that the auxiliary electrode and the plurality of color-separated electrodes are provided below the second electrode, the auxiliary electrode is provided on the thin film transistor layer, and the plurality of color-separated electrodes are provided on the light-emitting functional layer.

12. A display device according to any one of claims 1 to 11, characterized in that the first electrode is an anode, and the second electrode, the auxiliary electrode and the plurality of separate color electrodes are cathodes.

13. The display device according to any one of claims 1 to 12, wherein the arrangement of the plurality of sub-pixels is a diamond arrangement.

14. The display device according to any one of claims 1 to 13, further comprising a sealing film provided so as to cover the light emitting element layer.

15. The display device according to any one of claims 1 to 14, wherein the light emitting element layer is an organic electroluminescence element layer.

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